This document describes the software features for the HP A Series products and guides you through the
software configuration procedures. These configuration guides also provide configuration examples to
help you apply software features to different network scenarios.
This documentation is intended for network planners, field technical support and servicing engineers, and
network administrators working with the HP A Series products.
Part number: 5998-1501
Software version: A6600-CMW520-R2603
Document version: 6PW101-20110630
No part of this documentation may be reproduced or transmitted in any form or by any means without
prior written consent of Hewlett-Packard Development Company, L.P.
The information contained herein is subject to change without notice.
HEWLETT-PACKARD COMPANY MAKES NO WARRANTY OF ANY KIND WITH REGARD TO THIS
MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE. Hewlett-Packard shall not be liable for errors contained
herein or for incidental or consequential damages in connection with the furnishing, performance, or use
of this material.
The only warranties for HP products and services are set forth in the express warranty statements
accompanying such products and services. Nothing herein should be construed as constituting an
additional warranty. HP shall not be liable for technical or editorial errors or omissions contained herein.
Contents
MAC address table configuration ······························································································································ 1
How a MAC address table entry is created ·········································································································· 1
Types of MAC address table entries ······················································································································ 2
MAC address table-based frame forwarding ······································································································· 2
Configuring the MAC address table ······························································································································· 2
Configuring static, dynamic, and blackhole MAC address table entries ·························································· 2
Disabling MAC address learning ··························································································································· 3
Configuring the aging timer for dynamic MAC address entries ········································································· 4
Configuring the MAC learning limit on ports ········································································································ 5
Displaying and maintaining MAC address tables ········································································································ 5
MAC address table configuration example ··················································································································· 6
MAC information configuration ·································································································································· 8
How MAC information works ································································································································· 8
Configuring MAC information ········································································································································· 8
Enabling MAC information globally ······················································································································ 8
Enabling MAC information on an interface ·········································································································· 8
Configuring MAC information mode ····················································································································· 9
Configuring the interval for sending Syslog or trap messages ············································································ 9
Configuring the MAC information queue length ·································································································· 9
MAC information configuration example ······················································································································· 9
Ethernet link aggregation configuration ··················································································································· 11
Aggregating links in static mode ························································································································· 14
Aggregating links in dynamic mode ··················································································································· 15
Load sharing criteria for link aggregation groups ····························································································· 17
Ethernet link aggregation configuration task list ········································································································· 17
Configuring an aggregation group ····························································································································· 17
Configuring a static aggregation group ············································································································· 18
Configuring a dynamic aggregation group ······································································································· 19
Configuring an aggregate interface ···························································································································· 21
Configuring the description of an aggregate interface or subinterface ·························································· 21
Configuring the MTU of a Layer 3 aggregate interface or subinterface ························································· 22
Specifying a card to process or forward traffic for a Layer 3 aggregate interface ······································· 22
Enabling link state traps for an aggregate interface ························································································· 23
Shutting down an aggregate interface ··············································································································· 23
Configuring load sharing for link aggregation groups ······························································································ 24
Configuring the global link-aggregation load sharing criteria ········································································· 24
Configuring group-specific load sharing criteria ······························································································· 25
Displaying and maintaining Ethernet link aggregation ····························································································· 25
Ethernet link aggregation configuration examples ····································································································· 26
Layer 2 static aggregation configuration example ···························································································· 26
Layer 2 dynamic aggregation configuration example ······················································································ 28
Layer 2 aggregation load sharing configuration example ··············································································· 30
Layer 3 static aggregation configuration example ···························································································· 33
Layer 3 dynamic aggregation configuration example ······················································································ 34
Layer 3 aggregation load sharing configuration example ··············································································· 36
iii
Port isolation configuration ········································································································································ 39
Configuring an isolation group ···································································································································· 39
Assigning a port to the isolation group ·············································································································· 39
Displaying and maintaining isolation groups ············································································································· 39
Port isolation configuration example ··························································································································· 40
Protocol packets of STP ········································································································································· 41
Basic concepts in STP············································································································································ 41
How STP works ······················································································································································ 43
RSTP ················································································································································································· 48
MSTP ··············································································································································································· 49
Basic concepts in MSTP ········································································································································ 50
How MSTP works ·················································································································································· 53
Implementation of MSTP on devices ···················································································································· 54
Protocols and standards ······································································································································· 54
MSTP configuration task list ·········································································································································· 54
Configuring MSTP ·························································································································································· 56
Configuring an MST region ································································································································· 56
Configuring the root bridge or a secondary root bridge ·················································································· 57
Configuring the work mode of an MSTP device ································································································ 58
Configuring the priority of a device ···················································································································· 58
Configuring the maximum hops of an MST region ··························································································· 59
Configuring the network diameter of a switched network ················································································ 59
Configuring timers of MSTP ································································································································· 60
Configuring the timeout factor ····························································································································· 61
Configuring the maximum port rate ···················································································································· 61
Configuring ports as edge ports ·························································································································· 62
Configuring path costs of ports ···························································································································· 62
Configuring port priority ······································································································································· 65
Configuring the link type of ports ························································································································ 65
Configuring the mode a port uses to recognize/send MSTP packets ····························································· 66
Enabling the output of port state transition information ···················································································· 67
Enabling the MSTP feature ··································································································································· 67
Configuring basic settings of a VLAN interface ········································································································· 90
Port-based VLAN configuration ···································································································································· 91
Assigning an access port to a VLAN ·················································································································· 93
Assigning a trunk port to a VLAN ······················································································································· 94
Assigning a hybrid port to a VLAN ····················································································································· 95
Introduction to protocol-based VLAN ················································································································ 102
Configuring a protocol-based VLAN ················································································································· 103
Protocol-based VLAN configuration example ·································································································· 104
IP subnet-based VLAN configuration ·························································································································· 107
Configuring an IP subnet-based VLAN ············································································································· 107
Displaying and maintaining VLAN ···························································································································· 108
Super VLAN configuration ····································································································································· 109
Configuring a super VLAN ········································································································································· 109
Displaying and maintaining super VLAN ·················································································································· 111
Super VLAN configuration example ·························································································································· 111
Security mode and normal mode of voice VLANs ··························································································· 122
Configuring a voice VLAN ·········································································································································· 123
Background and benefits ···································································································································· 143
How QinQ works ················································································································································ 143
Implementations of QinQ ··································································································································· 145
Modifying the TPID in a VLAN tag ···················································································································· 145
Protocols and standards ····································································································································· 146
QinQ configuration task list ········································································································································ 146
Configuring basic QinQ ············································································································································· 147
Application scenarios ········································································································································· 160
VLAN termination configuration task list ··················································································································· 162
Configuring TPID for VLAN-tagged packets ·············································································································· 162
Introduction to TPID ············································································································································· 162
Configuring TPID on Layer 3 Ethernet/aggregate subinterfaces ··································································· 163
Enabling an ambiguous Dot1q/QinQ termination-enabled subinterface to transmit broadcasts and
multicasts ······································································································································································· 164
Configuring Dot1q termination ··································································································································· 165
Application scenario of one-to-one VLAN mapping ························································································ 179
Application scenario of one-to-two and two-to-two VLAN mapping ······························································ 180
Concepts and terms ············································································································································ 181
How LLDP works ·················································································································································· 203
Protocols and standards ····································································································································· 204
LLDP configuration task list ·········································································································································· 204
Performing basic LLDP configuration ·························································································································· 204
Configuring the advertisable TLVs ····················································································································· 206
Configuring the management address and its encoding format ···································································· 207
Setting other LLDP parameters ···························································································································· 208
Setting an encapsulation format for LLDPDUs ·································································································· 208
Configuring CDP compatibility ··································································································································· 209
Basic LLDP configuration example ····················································································································· 211
CDP-compatible LLDP configuration example ··································································································· 214
Support and other resources ·································································································································· 216
Contacting HP ······························································································································································ 216
Subscription service ············································································································································ 216
Related information ······················································································································································ 216
Index ········································································································································································ 219
vii
MAC address table configuration
The MAC address table configuration applies only to Layer 2 interfaces, including Layer 2 Ethernet
interfaces and Layer 2 aggregate interfaces.
This document covers only the configuration of unicast MAC address table entries, including static,
dynamic, and blackhole MAC address table entries. For more information about configuring static
multicast MAC address table entries, see IP Multicast Configuration Guide.
The SAP cards support the MAC address table configuration only when they work in Layer 2 mode.
An Ethernet router uses a MAC address table for forwarding frames through unicast instead of broadcast.
This table describes from which port a MAC address (or host) can be reached. When forwarding a frame,
the router first looks up the MAC address of the frame in the MAC address table for a match. If an entry is
found, the router forwards the frame out of the outgoing port in the entry. If no entry is found, the router
broadcasts the frame out of all but the incoming port.
How a MAC address table entry is created
The entries in the MAC address table come from two sources: automatically learned by the router and
manually added by the administrator.
MAC address learning
The router can populate its MAC address table automatically by learning the source MAC addresses of
incoming frames on each port.
When a frame arrives at a port, Port A for example, the router performs the following tasks:
1. Checks the source MAC address (for example, MAC-SOURCE) of the frame.
2. Looks up the MAC address in the MAC address table.
3. If an entry is found, updates the entry. If no entry is found, adds an entry for MAC-SOURCE and Port
A.
The router performs the learning process each time it receives a frame from an unknown source MAC
address, until the MAC address table is fully populated.
After learning the source MAC address of a frame, the router looks up the destination MAC address in
the MAC address table. If an entry is found for the MAC address, the router forwards the frame out of the
specific outgoing port. In this example, it is Port A.
Manually configuring MAC address entries
With dynamic MAC address learning, a router does not distinguish between illegitimate and legitimate
frames. This can invite security hazards. For example, when a hacker sends frames with a forged source
MAC address to a port different from the one to which the real MAC address is connected, the router
creates an entry for the forged MAC address, and forwards frames destined for the legal user to the
hacker instead.
To enhance the security of a port, manually add MAC address entries to the MAC address table of the
router to bind specific user devices to the port. Because manually configured entries have higher priority
than dynamically learned ones, you can prevent hackers from stealing data using forged MAC
addresses.
1
Types of MAC address table entries
A MAC address table can contain the following types of entries:
• Static entries, which are manually added and never age out.
• Dynamic entries, which can be manually added or dynamically learned and may age out.
• Blackhole entries, which are manually configured and never age out. Blackhole entries are
configured for filtering out frames with specific MAC addresses. For example, to block all packets
destined for a specific user for security concerns, configure the MAC address of this user as a
blackhole MAC address entry.
To adapt to network changes and prevent inactive entries from occupying table space, an aging
mechanism is adopted for dynamic MAC address entries. Each time a dynamic MAC address entry is
learned or created, an aging time starts. If the entry has not updated when the aging timer expires, the
router deletes the entry. If the entry has updated before the aging timer expires, the aging timer restarts.
A static or blackhole MAC address entry can overwrite a dynamic MAC address entry, but not vice
versa.
MAC address table-based frame forwarding
When forwarding a frame, the router adopts the following forwarding modes based on the MAC address
table:
• Unicast mode: If an entry is available for the destination MAC address, the router forwards the
frame out the outgoing interface indicated by the MAC address table entry.
• Broadcast mode: If the router receives a frame with the destination address being all ones, or no
entry is available for the destination MAC address, the router broadcasts the frame to all interfaces
except the receiving interface.
Configuring the MAC address table
These configuration tasks are all optional and can be performed in any order.
Configuring static, dynamic, and blackhole MAC address table
entries
To fence off MAC address spoofing attacks and improve port security, manually add MAC address table
entries to bind ports with MAC addresses.
Also, configure blackhole MAC address entries to filter out packets with certain MAC addresses.
2
Add or modify a static, dynamic, or blackhole MAC address table entry globally
To add or modify a static, dynamic, or blackhole MAC address table entry in system view:
Add or modify a static or dynamic MAC address table entry on an interface
To add or modify a static or dynamic MAC address table entry in interface view:
To do… Use the command… Remarks
1. Enter system view
2. Enter interface view
3. Add or modify a static or
dynamic MAC address entry
system-view —
interface interface-type interface-number
mac-address { dynamic | static }
mac-addressvlanvlan-id
—
Required.
Ensure that you have created the
VLAN and assign the interface to
the VLAN.
Required.
Use either command.
Ensure that you have
created the VLAN and
assign the interface to the
VLAN.
Disabling MAC address learning
You may need to disable MAC address learning sometimes to prevent the MAC address table from being
saturated. For example, you may need to do it when your router is being attacked by a large amount of
packets with different source MAC addresses.
Disabling global MAC address learning
Disabling global MAC address learning disables the learning function on all ports.
To disable MAC address learning:
To do… Use the command…Remarks
1. Enter system view
2. Disable global MAC address
learning
Disabling MAC address learning on ports
After enabling global MAC address learning, you may disable the function on a single port, or on all
ports in a port group as needed.
system-view —
mac-address mac-learning disable
Required
Enabled by default
3
To disable MAC address learning on an interface or a port group:
To do… Use the command…Remarks
1. Enter system view
system-view —
2. Enable global MAC address
learning
Enter Layer 2
3. Enter
interface
view or
port
group
view
4. Disable MAC address learning on
the interface or all ports in the port
group
Ethernet/aggregate
interface view
Enter port group view
For configuration about port groups, see the chapter “Ethernet interface configuration.”
Disabling MAC address learning on a VLAN
You may disable MAC address learning on a per-VLAN basis.
To disable MAC address learning on a VLAN:
To do… Use the command… Remarks
undo mac-address
mac-learning disable
interface interface-type interface-number
port-group manual
port-group-name
mac-address mac-learning
disable
Optional.
Enabled by default.
Required.
Use either command.
Settings in Layer 2
Ethernet/aggregate interface view
take effect on the current interface
only.
Settings in port group view take
effect on all member ports in the
port group.
Required.
By default, MAC address learning
is enabled on ports.
1. Enter system view
2. Enable global MAC address
learning
3. Enter VLAN view
4. Disable MAC address
learning on the VLAN
system-view —
undo mac-address mac-learning
disable
vlan vlan-id—
mac-address mac-learning disable
Optional
Enabled by default
Required
Enabled by default
Configuring the aging timer for dynamic MAC address entries
The MAC address table uses an aging timer for dynamic MAC address entries for security and efficient
use of table space. If a dynamic MAC address entry has failed to update before the aging timer expires,
the router deletes the entry. This aging mechanism ensures that the MAC address table could timely
update to accommodate latest network changes.
Set the aging timer appropriately. A long aging interval may cause the MAC address table to retain
outdated entries, exhaust the MAC address table resources, and fail to update its entries to accommodate
the latest network changes. A short interval may result in the removal of valid entries and unnecessary
broadcasts, which may affect router performance.
4
To configure the aging timer for dynamic MAC address entries:
To do… Use the command… Remarks
1. Enter system view
2. Configure the aging timer for
dynamic MAC address entries
system-view —
mac-address timer { aging
seconds | no-aging }
Optional
300 seconds by default
Reduce broadcasts on a stable network by disabling the aging timer to prevent dynamic entries from
aging out unnecessarily. By reducing broadcasts, you improve not only network performance, but also
security, because the chances for a data packet to reach unintended destinations are reduced.
Configuring the MAC learning limit on ports
As the MAC address table is growing, the forwarding performance of your router may degrade. To
prevent the MAC address table from getting so large that the forwarding performance is affected, limit
the number of MAC addresses that can be learned on a port.
To configure the MAC learning limit on a Layer 2 Ethernet interface, Layer 2 VE interface, Layer 2
aggregate interface, or all ports in a port group:
To do… Use the command… Remarks
1. Enter system view
Enter Layer 2
2. Enter
interface
view or
port
group
view
3. Configure the MAC learning limit
on the interface or port group, and
configure whether frames with
unknown source MAC addresses
can be forwarded or not when the
MAC learning limit is reached
Ethernet/aggregate
interface view
Enter port group view
system-view —
interface interface-type interface-number
port-group manual
port-group-name
mac-address max-mac-count
count
Required.
Use either command.
Settings in Layer 2
Ethernet/aggregate interface
view take effect on the current
interface only.
Settings in port group view take
effect on all member ports in the
port group.
Required.
By default, the MAC learning
limit is not configured on ports.
# Display information about the blackhole MAC address table.
[Router] display mac-address blackhole
MAC ADDR VLAN ID STATE PORT INDEX AGING TIME
000f-e235-abcd 1 Blackhole N/A NOAGED
--- 1 mac address(es) found ---
# View the aging time of dynamic MAC address entries.
[Router] display mac-address aging-time
Mac address aging time: 500s
7
MAC information configuration
The SAP cards support this feature only when they work in Layer 2 mode.
To monitor a network, you need to monitor users joining and leaving the network. Because a MAC
address uniquely identifies a network user, monitor those users joining and leaving a network by
monitoring their MAC addresses.
With the MAC information function, Layer 2 Ethernet interfaces send Syslog or trap messages to the
monitor end in the network when they learn or delete MAC addresses. By analyzing these messages, the
monitor end can monitor users accessing the network.
How MAC information works
When a new MAC address is learned or an existing MAC address is deleted on a router, the router
writes related information about the MAC address to the buffer area used to store user information.
When the timer set for sending MAC address monitoring Syslog or trap messages expires, or when the
buffer is used up, the router sends the Syslog or trap messages to the monitor end immediately.
Configuring MAC information
Enabling MAC information globally
To enable MAC information globally:
To do… Use the command…Remarks
1. Enter system view
2. Enable MAC information
globally
Enabling MAC information on an interface
To enable MAC information on an interface:
To do… Use the command…Remarks
1. Enter system view
2. Enter Layer 2 Ethernet
interface view
3. Enable MAC information on
the interface
system-view —
mac-address information enable
system-view —
interface interface-type interface-number
mac-address information enable
{ added | deleted }
Required
Disabled by default
—
Required
Disabled by default
To enable MAC information on an Ethernet interface, enable MAC information globally first.
8
Configuring MAC information mode
To configure MAC information mode:
To do… Use the command…Remarks
1. Enter system view
system-view —
2. Configure MAC information
mode
mac-address information mode
{ syslog | trap }
Optional
trap by default
Configuring the interval for sending Syslog or trap messages
To prevent Syslog or trap messages from being sent too frequently, set the interval for sending Syslog or
trap messages.
To set the interval for sending Syslog or trap messages:
To do… Use the command…Remarks
1. Enter system view
2. Set the interval for sending
Syslog or trap messages
system-view
mac-address information interval
interval-time
—
Optional
One second by default
Configuring the MAC information queue length
To avoid losing user MAC address information, when the buffer storing user MAC address information is
used up, the user MAC address information in the buffer is sent to the monitor end in the network, even if
the timer set for sending MAC address monitoring Syslog or trap messages has not expired yet.
To configure the MAC information queue length:
To do… Use the command…Remarks
1. Enter system view
2. Configure the MAC
information queue length
system-view —
mac-address information
queue-length value
Optional
50 by default
MAC information configuration example
Network requirements
As shown in Figure 2:
• Host A is connected to a remote server (Server) through Router.
• Enable MAC information on GigabitEthernet 4/0/1 on Router. Router sends MAC address changes
in Syslog messages to Host B through GigabitEthernet 4/0/3. Host B analyzes and displays the
Syslog messages.
9
Figure 2 Network diagram for MAC information configuration
Configuration procedure
1. Configure Router to send Syslog messages to Host B.
For more information, see Network Management and Monitoring Configuration Guide.
2. Enable MAC information.
# Enable MAC information on Router.
<Router> system-view
[Router] mac-address information enable
# Configure MAC information mode as Syslog.
[Router] mac-address information mode syslog
# Enable MAC information on GigabitEthernet 4/0/1.
[Router] interface gigabitethernet 4/0/1
[Router-GigabitEthernet4/0/1] mac-address information enable added
[Router-GigabitEthernet4/0/1] mac-address information enable deleted
[Router-GigabitEthernet4/0/1] quit
# Set the MAC information queue length to 100.
[Router] mac-address information queue-length 100
# Set the interval for sending Syslog or trap messages to 20 seconds.
[Router] mac-address information interval 20
10
Ethernet link aggregation configuration
The SAP cards support the feature only when they work in Layer 2 mode.
The SAP cards can be installed on distributed routers only.
Ethernet link aggregation, or simply link aggregation, combines multiple physical Ethernet ports into one
logical link, called an aggregate link. Link aggregation delivers the following benefits:
• Increases bandwidth beyond the limits of any single link. In an aggregate link, traffic is distributed
across the member ports.
• Improves link reliability. The member ports back up one another dynamically. When a member port
fails, its traffic is switched to other member ports automatically.
As shown in Figure 3, Devic
physical Ethernet links are combined into an aggregate link, Link aggregation 1. The bandwidth of this
aggregate link is as high as the total bandwidth of these three physical Ethernet links. At the same time,
the three Ethernet links back up one another.
Figure 3 Diagram for Ethernet link aggregation
e A and Device B are connected by three physical Ethernet links. These
Basic concepts
Aggregation group, member port, aggregate interface
Link aggregation is implemented through link aggregation groups. An aggregation group is a group of
Ethernet interfaces combined together, which are called member ports of the aggregation group. For
each aggregation group, a logical interface, called an aggregate interface, is created. To an upper layer
entity that uses the link aggregation service, a link aggregation group looks like a single logical link and
data traffic is transmitted through the aggregate interface.
Aggregate interfaces have the following types: BAGG interfaces, also called Layer 2 aggregate
interfaces, and RAGG interfaces, also called Layer 3 aggregate interfaces. When you create an
aggregate interface, the switch automatically creates an aggregation group of the same type and number
as the aggregate interface. For example, when you create interface Bridge-aggregation 1, Layer 2
aggregation group 1 is created.
Assign Layer 2 Ethernet interfaces only to a Layer 2 aggregation group, and Layer 3 Ethernet interfaces
only to a Layer 3 aggregation group.
On a Layer 3 aggregate interface, you can create subinterfaces. These subinterfaces are logical
interfaces that operate at the network layer. They can receive VLAN tagged packets for their Layer 3
aggregate interface.
The rate of an aggregate interface equals the total rate of its member ports in the selected state, and its
duplex mode is the same as the selected member ports. For more information about the states of member
ports in an aggregation group, see “Aggregation states of member ports in an aggregation group.”
11
Aggregation states of member ports in an aggregation group
A member port in an aggregation group can be in either of the following aggregation states:
• Selected: A selected port can forward user traffic.
• Unselected: An unselected port cannot forward user traffic.
Operational key
When aggregating ports, the system automatically assigns each port an operational key based on port
information such as port rate and duplex mode. Any change to this information triggers a recalculation of
the operational key.
In an aggregation group, all selected member ports are assigned the same operational key.
Configuration classes
Every configuration setting on a port may affect its aggregation state. Port configurations fall into the
following classes:
• Port attribute configurations, including port rate, duplex mode, and link status (up/down), which are
the most basic port configurations.
• Class-two configurations, as described in Table 1. A member port c
an be placed in the selected
state only if it has the same class-two configurations as the aggregate interface.
Table 1 Class-two configurations
Feature Considerations
Port isolation
QinQ
VLAN
MAC address learning
Whether the port has joined an isolation group, and the isolation group to
which the port belongs
QinQ enable state (enable/disable), TPID for VLAN tags, outer VLAN tags to be
added, inner-to-outer VLAN priority mappings, inner-to-outer VLAN tag
mappings, inner VLAN ID substitution mappings
Permitted VLAN IDs, PVID, link type (trunk, hybrid, or access), IP subnet-based
VLAN configuration, protocol-based VLAN configuration, VLAN tagging mode
MAC address learning capability, MAC address learning limit, forwarding of
frames with unknown destination MAC addresses after the MAC address
learning limit is reached
Class-two configurations made on an aggregate interface are automatically synchronized to all its
member ports. These configurations are retained on the member ports even after the aggregate interface
is removed.
Any class-two configuration change may affect the aggregation state of link aggregation member ports
and ongoing traffic. To make sure that you are aware of the risk, the system displays a warning message
every time you attempt to change a class-two configuration setting on a member port.
• Class-one configurations do not affect the aggregation state of the member port even if they are
different from those on the aggregate interface. GVRP and MSTP settings are examples of class-one
configurations.
The class-one configuration for a member port is effective only when the member port leaves the
aggregation group.
12
yp
Reference port
When setting the aggregation state of the ports in an aggregation group, the system automatically picks
a member port as the reference port. A selected port must have the same port attributes and class-two
configurations as the reference port.
LACP
The IEEE 802.3ad LACP enables dynamic aggregation of physical links. It uses LACPDUs for exchanging
aggregation information between LACP-enabled devices.
1. LACP functions
Table 2 LACP functions
Category Description
Basic LACP functions
2. LACP priorities
Implemented through the basic LACPDU fields, including the system LACP priority,
system MAC address, port aggregation priority, port number, and operational
key.
Each member port in a LACP-enabled aggregation group exchanges information
with its peer. When a member port receives an LACPDU, it compares the received
information with the information received on the other member ports. In this way
the two systems reach an agreement on which ports should be placed in the
selected state.
LACP priorities have the following types: system LACP priority and port aggregation priority, as described
in Table 3.
Table 3 LACP priorities
T
e Description Remarks
Used by two peer devices (or systems) to determine which one is
System LACP
priority
Port aggregation
priority
3. LACP timeout interval
superior in link aggregation.
In dynamic link aggregation, the system that has higher system LACP
priority sets the selected state of member ports on its side first and
then the system that has lower priority sets port state accordingly.
Determines the likelihood of a member port to be selected on a
system. The higher port aggregation priority, the higher likelihood.
The smaller the
priority value,
the higher the
priority
The LACP timeout interval specifies how long a member port waits to receive LACPDUs from the peer port.
If a local member port fails to receive LACPDUs from the peer within three times the LACP timeout interval,
the member port assumes that the peer port has failed. Configure the LACP timeout interval as the short
timeout interval (1 second) or the long timeout interval (30 seconds).
13
p
Link aggregation modes
Link aggregation has the following modes: dynamic and static. Dynamic link aggregation uses LACP and
static link aggregation does not. Table 4 c
Table 4 A comparison between static and dynamic aggregation modes
ompares the two aggregation modes.
Aggregatio
n mode
Static Disabled
Dynamic Enabled
LACP status on
member
orts
Pros Cons
Aggregation is stable. The
aggregation state of the member
ports are not affected by the peer
ports.
The administrator does not need to
maintain link aggregations. The
peer systems maintain the
aggregation state of the member
ports automatically.
In a dynamic link aggregation group:
• A selected port can receive and send LACPDUs.
• An unselected port can receive and send LACPDUs only if it is up and has the same class-two
configurations as the aggregate interface.
Aggregating links in static mode
LACP is disabled on the member ports in a static aggregation group. You must manually maintain the
aggregation state of the member ports.
The member ports do not adjust
the aggregation state according to
that of the peer ports. The
administrator must manually
maintain link aggregations.
Aggregation is unstable. The
aggregation state of member ports
is susceptible to network changes.
The static link aggregation procedure comprises:
• Selecting a reference port
• Setting the aggregation state of each member port
Selecting a reference port
The system selects a reference port from the member ports that are in the up state and have the same
class-two configurations as the aggregate interface.
The candidate ports are sorted by aggregation priority, duplex, and speed in this order: lowest
aggregation priority value, full duplex/high speed, full duplex/low speed, half duplex/high speed, and
half duplex/low speed. The one at the top is selected as the reference port. If two ports have the same
aggregation priority, duplex mode, and speed, the one with the lower port number wins out.
Setting the aggregation state of each member port
After selecting the reference port, the static aggregation group sets the aggregation state of each member
port, as shown in Figure 4.
14
Figure 4 Set the aggregation state of a member port in a static aggregation group
To ensure stable aggregation state and service continuity, do not change port attributes or class-two
configurations on any member port.
If a static aggregation group has reached the limit on selected ports, any port joins the group is placed in
the unselected state to avoid traffic interruption on the current selected ports. Avoid this situation, however,
because it may cause the aggregation state of a port to change after a reboot.
Aggregating links in dynamic mode
LACP is automatically enabled on all member ports in a dynamic aggregation group. The protocol
automatically maintains the aggregation state of ports.
The dynamic link aggregation procedure comprises:
• Selecting a reference port
• Setting the aggregation state of each member port
Selecting a reference port
The local system (the actor) and the remote system (the partner) negotiate a reference port using the
following workflow:
1. Compare the system ID (comprising the system LACP priority and the system MAC address). The
system with the lower LACP priority value wins out. If they are the same, compare the system MAC
addresses. The system with the lower MAC address wins.
2. The system with the smaller system ID selects the port with the smallest port ID as the reference port.
A port ID comprises a port aggregation priority and a port number. The port with the lower
15
aggregation priority value wins out. If two ports have the same aggregation priority, the system
compares their port numbers. The port with the smaller port number wins.
Setting the aggregation state of each member port
After the reference port is selected, the system with the lower system ID sets the state of each member port
in the dynamic aggregation group on its side as shown in Figure 5.
Figure 5 Set the state o
f a member port in a dynamic aggregation group
Meanwhile, the system with the higher system ID, being aware of the aggregation state changes on the
remote system, sets the aggregation state of local member ports the same as their peer ports.
To ensure stable aggregation state and service continuity, do not change port attributes or class-two
configurations on any member port.
In a dynamic aggregation group, when the aggregation state of a local port changes, the aggregation
state of the peer port also changes.
A port that joins a dynamic aggregation group after the selected port limit has been reached is placed in
the selected state if it is more eligible for being selected than a current member port.
16
Load sharing criteria for link aggregation groups
In a link aggregation group, traffic may be load-shared across the selected member ports based on a set
of criteria, depending on your configuration.
Choose one of the following criteria or any combination for load sharing:
• MAC addresses
• IP addresses
Alternatively, configure the system to perform per-packet link aggregation.
Ethernet link aggregation configuration task list
Complete the following tasks to configure Ethernet link aggregation:
Task Remarks
Configuring an
aggregation
group
Configuring an
aggregate
interface
Configuring load
sharing for link
aggregation
groups
Configuring a static aggregation group
Configuring a dynamic aggregation group
Configuring the description of an aggregate interface or
subinterface
Configuring the MTU of a Layer 3 aggregate interface or
subinterface
Specifying a card to process or forward traffic for a Layer
3 aggregate interface
Enabling link state traps for an aggregate interface Optional
Shutting down an aggregate interface Optional
Configuring the global link-aggregation load sharing
criteria
Choose to create a Layer 2 or Layer 3 link aggregation group depending on the ports to be aggregated:
Select either task
Optional
Optional
Optional
Optional
• To aggregate Layer 2 Ethernet interfaces, create a Layer 2 link aggregation group.
• To aggregate Layer 3 Ethernet interfaces, create a Layer 3 link aggregation group.
Configuration guidelines
Removing an aggregate interface also removes the corresponding aggregation group. At the same time,
all member ports leave the aggregation group.
You cannot assign a port to a Layer 2 aggregation group if any of the features listed in Table 5 is
conf
igured on the port.
17
Table 5 Features incompatible with Layer 2 aggregation groups
Feature Reference
RRPP RRPP in the High Availability Configuration Guide
MAC authentication
Port security Port security in the Security Configuration Guide
Packet filtering Firewall in the Security Configuration Guide
Ethernet frame filtering Firewall in the Security Configuration Guide
IP source guard IP source guard in the Security Configuration Guide
802.1X 802.1X in the Security Configuration Guide
Ports specified as source
interfaces in portal-free rules
MAC authentication in the Security Configuration Guide
Portal in the Security Configuration Guide
You cannot assign a port to a Layer 3 aggregation group if any of the features listed in Table 6 is
configured on the port.
Table 6 Interfaces that cannot be assigned to a Layer 3 aggregation group
Interface type Reference
Interfaces configured with IP addresses IP addressing in the Layer 3—IP Services Configuration Guide
Interfaces configured as DHCP/BOOTP
clients
DHCP in the Layer 3—IP Services Configuration Guide
VRRP VRRP in the High Availability Configuration Guide
Portal Portal in the Security Configuration Guide
If a port is used as a reflector port for port mirroring, do not assign it to an aggregation group. For more
information about reflector ports, see Network Management and Monitoring Configuration Guide.
Configuring a static aggregation group
To guarantee a successful static aggregation, make sure that the ports at both ends of each link are in the
same aggregation state.
Configuring a Layer 2 static aggregation group
To configure a Layer 2 static aggregation group:
To do... Use the command... Remarks
1. Enter system view
2. Create a Layer 2 aggregate
interface and enter Layer 2
aggregate interface view
system-view —
interface bridge-aggregation
interface-number
Required.
When you create a Layer 2
aggregate interface, the system
automatically creates a Layer 2
static aggregation group
numbered the same.
3. Exit to system view
quit —
18
To do... Use the command... Remarks
4. Enter Layer 2 Ethernet
interface view
5. Assign the Ethernet interface
to the aggregation group
interface interface-type
interface-number
port link-aggregation group
number
Configuring a Layer 3 static aggregation group
To configure a Layer 3 static aggregation group:
To do... Use the command... Remarks
1. Enter system view
2. Create a Layer 3 aggregate
interface and enter Layer 3
aggregate interface view
3. Exit to system view
4. Enter Layer 3 Ethernet
interface view
5. Assign the Ethernet interface
to the aggregation group
system-view —
interface route-aggregation
interface-number
quit —
interface interface-type
interface-number
port link-aggregation group
number
Required.
Repeat these two steps to assign
more Layer 2 Ethernet interfaces to
the aggregation group.
Required.
When you create a Layer 3
aggregate interface, the system
automatically creates a Layer 3
static aggregation group
numbered the same.
Required.
Repeat these two steps to assign
more Layer 3 Ethernet interfaces to
the aggregation group.
Configuring a dynamic aggregation group
To guarantee a successful dynamic aggregation, make sure that the peer ports of the ports aggregated at
one end are also aggregated. The two ends can automatically negotiate the aggregation state of each
member port.
Configuring a Layer 2 dynamic aggregation group
To configure a Layer 2 dynamic aggregation group:
To do... Use the command... Remarks
1. Enter system view
2. Set the system LACP priority
system-view —
lacp system-priority system-priority
Optional.
By default, the system LACP
priority is 32,768.
Changing the system LACP priority
may affect the aggregation state
of the ports in a dynamic
aggregation group.
19
To do... Use the command... Remarks
Required.
3. Create a Layer 2 aggregate
interface and enter Layer 2
aggregate interface view
interface bridge-aggregation
interface-number
When you create a Layer 2
aggregate interface, the system
automatically creates a Layer 2
static aggregation group
numbered the same.
4. Configure the aggregation
group to work in dynamic
aggregation mode
5. Exit to system view
6. Enter Layer 2 Ethernet
interface view
7. Assign the Ethernet interface
to the aggregation group
8. Assign the port an
aggregation priority
9. Set the LACP timeout interval
on the port to the short timeout
interval (1 second)
Required.
link-aggregation mode dynamic
quit —
interface interface-type
interface-number
port link-aggregation group
number
link-aggregation port-priority
port-priority
lacp period short
By default, an aggregation group
works in static aggregation mode.
Required.
Repeat these two steps to assign
more Layer 2 Ethernet interfaces to
the aggregation group.
Optional.
By default, the aggregation
priority of a port is 32,768.
Changing the aggregation priority
of a port may affect the
aggregation state of the ports in
the dynamic aggregation group.
Optional.
By default, the LACP timeout
interval on a port is the long
timeout interval (30 seconds).
Configuring a Layer 3 dynamic aggregation group
To configure a Layer 3 dynamic aggregation group:
To do... Use the command... Remarks
1. Enter system view
2. Set the system LACP
priority
3. Create a Layer 3
aggregate interface and
enter Layer 3 aggregate
interface view
system-view —
lacp system-priority system-priority
interface route-aggregation
interface-number
20
Optional.
By default, the system LACP priority is
32,768.
Changing the system LACP priority may
affect the aggregation state of the ports
in the dynamic aggregation group.
Required.
When you create a Layer 3 aggregate
interface, the system automatically
creates a Layer 3 static aggregation
group numbered the same.
To do... Use the command... Remarks
4. Configure the
aggregation group to
work in dynamic
aggregation mode
link-aggregation mode dynamic
Required.
By default, an aggregation group works
in static aggregation mode.
5. Exit to system view
6. Enter Layer 3 Ethernet
interface view
7. Assign the Ethernet
interface to the
aggregation group
8. Assign the port an
aggregation priority
9. Set the LACP timeout
interval on the port to the
short timeout interval (1
second)
quit —
interface interface-type
interface-number
port link-aggregation group
number
link-aggregation port-priority
port-priority
lacp period short
Required.
Repeat these two steps to assign more
Layer 3 Ethernet interfaces to the
aggregation group.
Optional.
By default, the aggregation priority of a
port is 32,768.
Changing the aggregation priority of a
port may affect the aggregation state of
ports in the dynamic aggregation group.
Optional.
By default, the LACP timeout interval on a
port is the long timeout interval (30
seconds).
Configuring an aggregate interface
Perform the following configurations on an aggregate interface:
• Configuring the description of an aggreg
• Configuring the MTU of a Layer 3 aggregate interface or su
• Specifying a card to process or forward traffic
ate interface or subinterface
binterface
for a Layer 3 aggregate interface
• Enabling link state traps for an aggregate interface
• Shutting down an aggregate interface
In addition to the prec
eding configurations, most of the configurations that can be performed on Layer 2
or Layer 3 Ethernet interfaces can also be performed on Layer 2 or Layer 3 aggregate interfaces.
Configuring the description of an aggregate interface or
subinterface
Configure the description of an aggregate interface for administration purposes such as describing the
purpose of the interface.
To configure the description of an aggregate interface or subinterface:
To do... Use the command... Remarks
1. Enter system view
system-view —
21
To do... Use the command... Remarks
Enter Layer 2
aggregate
2. Enter
aggregate
interface
view
3. Configure the description
of the aggregate interface
or subinterface
interface view
Enter Layer 3
aggregate
interface or
subinterface
view
interface bridge-aggregation
interface-number
interface route-aggregation
{ interface-number |
interface-number.subnumber }
descriptiontext
Use either command.
Optional.
By default, the description of an
interface is in the format of
interface-name Interface, such as
Bridge-Aggregation1 Interface.
Configuring the MTU of a Layer 3 aggregate interface or
subinterface
The MTU of an interface affects IP packets fragmentation and reassembly on the interface.
To change the MTU of a Layer 3 aggregate interface or subinterface:
To do... Use the command... Remarks
1. Enter system view
2. Enter Layer 3 aggregate
interface or subinterface view
3. Configure the MTU of the
Layer 3 aggregate interface
or subinterface
system-view —
interface route-aggregation
{ interface-number |
interface-number.subnumber }
mtusize
—
Optional
1500 bytes by default
Specifying a card to process or forward traffic for a Layer 3
aggregate interface
If you do not specify a card to process or forward traffic for a Layer 3 aggregate interface whose member
ports are located on different cards, the traffic may be processed or forwarded by different cards from
time to time due to changes in the selected ports.
If you unplug the card configured to process traffic for a Layer 3 aggregate interface, traffic on the Layer
3 aggregate interface is interrupted. After you plug the card back in, the traffic is restored.
On a distributed router, use this feature to specify a card to process or forward traffic for a Layer 3
aggregate interface.
22
To specify a card to process or forward traffic for a Layer 3 aggregate interface:
To do... Use the command... Remarks
1. Enter system view
2. Enter Layer 3 aggregate
interface view
3. Specify a card to process or
forward traffic for the current
interface
system-view —
interface route-aggregation
interface-number
service slot slot-number
—
Required.
By default, traffic on a Layer 3
aggregate interface whose member
ports are located on the same card is
processed or forwarded by the card
that houses the member ports, and
traffic on a Layer 3 aggregate interface
whose member ports are located on
different cards is processed or
forwarded by the card that houses the
first selected member port.
Enabling link state traps for an aggregate interface
Configure an aggregate interface to generate linkUp trap messages when its link goes up and linkDown
trap messages when its link goes down. For more information, see Network Management and Monitoring Configuration Guide.
To enable link state traps on an aggregate interface:
To do... Use the command... Remarks
1. Enter system view
2. Enable the trap function
globally
Enter Layer 2
aggregate
3. Enter
aggregate
interface
view
4. Enable link state traps for
the aggregate interface
interface view
Enter Layer 3
aggregate
interface or
subinterface
view
Shutting down or bringing up an aggregate interface affects the aggregation state and link state of ports
in the corresponding aggregation group in the following ways:
—
Optional.
By default, link state trapping is
enabled globally and on all
interfaces.
Required.
Use either command.
Optional.
Enabled by default.
• When an aggregate interface is shut down, all selected ports in the corresponding aggregation
group become unselected and their link state becomes down.
23
Loading...
+ 193 hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.