Red Hat ENTERPRISE LINUX 4 - ADMINISTRATION User Manual

Red Hat Enterprise Linux 4

Cluster Administration

Configuring and Managing a Red Hat Cluster

Cluster Administration

Red Hat Enterprise Linux 4 Cluster Administration Configuring and Managing a Red Hat Cluster Edition 1.0

Copyright © 2009 Red Hat, Inc. This material may only be distributed subject to the terms and conditions set forth in the Open Publication License, V1.0 or later (the latest version of the OPL is presently available at http://www.opencontent.org/openpub/).

Red Hat and the Red Hat "Shadow Man" logo are registered trademarks of Red Hat, Inc. in the United States and other countries.

All other trademarks referenced herein are the property of their respective owners.

1801 Varsity Drive Raleigh, NC 27606-2072 USA Phone: +1 919 754 3700 Phone: 888 733 4281 Fax: +1 919 754 3701 PO Box 13588 Research Triangle Park, NC 27709 USA

Configuring and Managing a Red Hat Cluster describes the configuration and management of Red Hat cluster systems for Red Hat Enterprise Linux 4. It does not include information about Red Hat Linux Virtual Servers (LVS). Information about installing and configuring LVS is in a separate document.

iii

Introduction v

1. Document Conventions ................................................................................................... vi

1.1. Typographic Conventions ..................................................................................... vi

1.2. Pull-quote Conventions ....................................................................................... viii

1.3. Notes and Warnings ........................................................................................... viii

2. Feedback ....................................................................................................................... ix

1. Red Hat Cluster Configuration and Management Overview 1

1.1. Configuration Basics ..................................................................................................... 1

1.1.1. Setting Up Hardware ......................................................................................... 1

1.1.2. Installing Red Hat Cluster software ..................................................................... 2

1.1.3. Configuring Red Hat Cluster Software ................................................................ 2

1.2. Conga ......................................................................................................................... 4

1.3. system-config-cluster Cluster Administration GUI ........................................................... 6

1.3.1. Cluster Configuration Tool .................................................................................. 7

1.3.2. Cluster Status Tool ............................................................................................ 8

1.4. Command Line Administration Tools ............................................................................. 9

2. Before Configuring a Red Hat Cluster 11

2.1. Compatible Hardware ................................................................................................. 11

2.2. Enabling IP Ports ....................................................................................................... 11

2.2.1. Enabling IP Ports on Cluster Nodes .................................................................. 11

2.2.2. Enabling IP Ports on Computers That Run luci .................................................. 12

2.2.3. Examples of iptables Rules .............................................................................. 13

2.3. Configuring ACPI For Use with Integrated Fence Devices ............................................. 14

2.3.1. Disabling ACPI Soft-Off with chkconfig Management .......................................... 15

2.3.2. Disabling ACPI Soft-Off with the BIOS .............................................................. 16

2.3.3. Disabling ACPI Completely in the grub.conf File ................................................ 18

2.4. Configuring max_luns ................................................................................................. 19

2.5. Considerations for Using Quorum Disk ........................................................................ 20

2.6. Red Hat Cluster Suite and SELinux ............................................................................. 21

2.7. Considerations for Using Conga .................................................................................. 21

2.8. General Configuration Considerations .......................................................................... 22

3. Configuring Red Hat Cluster With Conga 23

3.1. Configuration Tasks .................................................................................................... 23

3.2. Starting luci and ricci .................................................................................................. 23

3.3. Creating A Cluster ...................................................................................................... 25

3.4. Global Cluster Properties ............................................................................................ 26

3.5. Configuring Fence Devices ......................................................................................... 28

3.5.1. Creating a Shared Fence Device ...................................................................... 29

3.5.2. Modifying or Deleting a Fence Device ............................................................... 31

3.6. Configuring Cluster Members ...................................................................................... 31

3.6.1. Initially Configuring Members ............................................................................ 31

3.6.2. Adding a Member to a Running Cluster ............................................................ 32

3.6.3. Deleting a Member from a Cluster .................................................................... 33

3.7. Configuring a Failover Domain .................................................................................... 34

3.7.1. Adding a Failover Domain ................................................................................ 35

3.7.2. Modifying a Failover Domain ............................................................................ 36

3.8. Adding Cluster Resources .......................................................................................... 37

3.9. Adding a Cluster Service to the Cluster ....................................................................... 39

3.10. Configuring Cluster Storage ...................................................................................... 40

Cluster Administration

4. Managing Red Hat Cluster With Conga 43

4.1. Starting, Stopping, and Deleting Clusters ..................................................................... 43

4.2. Managing Cluster Nodes ............................................................................................ 44

4.3. Managing High-Availability Services ............................................................................ 45

4.4. Diagnosing and Correcting Problems in a Cluster ......................................................... 46

5. Configuring Red Hat Cluster With system-config-cluster 47

5.1. Configuration Tasks .................................................................................................... 47

5.2. Starting the Cluster Configuration Tool ........................................................................ 48

5.3. Configuring Cluster Properties ..................................................................................... 52

5.4. Configuring Fence Devices ......................................................................................... 53

5.5. Adding and Deleting Members .................................................................................... 54

5.5.1. Adding a Member to a New Cluster .................................................................. 54

5.5.2. Adding a Member to a Running DLM Cluster .................................................... 56

5.5.3. Deleting a Member from a DLM Cluster ............................................................ 58

5.5.4. Adding a GULM Client-only Member ................................................................. 60

5.5.5. Deleting a GULM Client-only Member ............................................................... 60

5.5.6. Adding or Deleting a GULM Lock Server Member .............................................. 62

5.6. Configuring a Failover Domain .................................................................................... 64

5.6.1. Adding a Failover Domain ................................................................................ 65

5.6.2. Removing a Failover Domain ........................................................................... 67

5.6.3. Removing a Member from a Failover Domain .................................................... 68

5.7. Adding Cluster Resources .......................................................................................... 68

5.8. Adding a Cluster Service to the Cluster ....................................................................... 71

5.9. Propagating The Configuration File: New Cluster ......................................................... 74

5.10. Starting the Cluster Software ..................................................................................... 74

6. Managing Red Hat Cluster With system-config-cluster 77

6.1. Starting and Stopping the Cluster Software .................................................................. 77

6.2. Managing High-Availability Services ............................................................................ 77

6.3. Modifying the Cluster Configuration ............................................................................. 79

6.4. Backing Up and Restoring the Cluster Database .......................................................... 80

6.5. Disabling the Cluster Software .................................................................................... 81

6.6. Diagnosing and Correcting Problems in a Cluster ......................................................... 82

A. Example of Setting Up Apache HTTP Server 83

A.1. Apache HTTP Server Setup Overview ........................................................................ 83

A.2. Configuring Shared Storage ........................................................................................ 83

A.3. Installing and Configuring the Apache HTTP Server ..................................................... 84

B. Fence Device Parameters 87

C. Revision History 93

Index 95

Introduction

This document provides information about installing, configuring and managing Red Hat Cluster components. Red Hat Cluster components are part of Red Hat Cluster Suite and allow you to connect a group of computers (called nodes or members) to work together as a cluster. This document does not include information about installing, configuring, and managing Linux Virtual Server (LVS) software. Information about that is in a separate document.

The audience of this document should have advanced working knowledge of Red Hat Enterprise Linux and understand the concepts of clusters, storage, and server computing.

This document is organized as follows:

• Chapter 1, Red Hat Cluster Configuration and Management Overview

• Chapter 2, Before Configuring a Red Hat Cluster

• Chapter 3, Configuring Red Hat Cluster With Conga

• Chapter 4, Managing Red Hat Cluster With Conga

• Chapter 5, Configuring Red Hat Cluster With system-config-cluster

• Chapter 6, Managing Red Hat Cluster With system-config-cluster

• Appendix A, Example of Setting Up Apache HTTP Server

• Appendix B, Fence Device Parameters

• Appendix C, Revision History

For more information about Red Hat Enterprise Linux 4, refer to the following resources:

• Red Hat Enterprise Linux Installation Guide — Provides information regarding installation.

• Red Hat Enterprise Linux Introduction to System Administration — Provides introductory information for new Red Hat Enterprise Linux system administrators.

• Red Hat Enterprise Linux System Administration Guide — Provides more detailed information about configuring Red Hat Enterprise Linux to suit your particular needs as a user.

• Red Hat Enterprise Linux Reference Guide — Provides detailed information suited for more experienced users to reference when needed, as opposed to step-by-step instructions.

• Red Hat Enterprise Linux Security Guide — Details the planning and the tools involved in creating a secured computing environment for the data center, workplace, and home.

For more information about Red Hat Cluster Suite for Red Hat Enterprise Linux 4 and related products, refer to the following resources:

• Red Hat Cluster Suite Overview — Provides a high level overview of the Red Hat Cluster Suite.

• LVM Administrator's Guide: Configuration and Administration — Provides a description of the Logical Volume Manager (LVM), including information on running LVM in a clustered environment.

Introduction

• Global File System: Configuration and Administration — Provides information about installing, configuring, and maintaining Red Hat GFS (Red Hat Global File System).

• Using Device-Mapper Multipath — Provides information about using the Device-Mapper Multipath feature of Red Hat Enterprise Linux 4.7.

• Using GNBD with Global File System — Provides an overview on using Global Network Block Device (GNBD) with Red Hat GFS.

• Linux Virtual Server Administration — Provides information on configuring high-performance systems and services with the Linux Virtual Server (LVS).

• Red Hat Cluster Suite Release Notes — Provides information about the current release of Red Hat Cluster Suite.

Red Hat Cluster Suite documentation and other Red Hat documents are available in HTML, PDF, and RPM versions on the Red Hat Enterprise Linux Documentation CD and online at http://

www.redhat.com/docs/.

1. Document Conventions

This manual uses several conventions to highlight certain words and phrases and draw attention to specific pieces of information.

In PDF and paper editions, this manual uses typefaces drawn from the Liberation Fonts1 set. The Liberation Fonts set is also used in HTML editions if the set is installed on your system. If not, alternative but equivalent typefaces are displayed. Note: Red Hat Enterprise Linux 5 and later includes the Liberation Fonts set by default.

1.1. Typographic Conventions

Four typographic conventions are used to call attention to specific words and phrases. These conventions, and the circumstances they apply to, are as follows.

Mono-spaced Bold

Used to highlight system input, including shell commands, file names and paths. Also used to highlight key caps and key-combinations. For example:

To see the contents of the file my_next_bestselling_novel in your current working directory, enter the cat my_next_bestselling_novel command at the shell prompt and press Enter to execute the command.

The above includes a file name, a shell command and a key cap, all presented in Mono-spaced Bold and all distinguishable thanks to context.

Key-combinations can be distinguished from key caps by the hyphen connecting each part of a keycombination. For example:

Press Enter to execute the command.

Press Ctrl+Alt+F1 to switch to the first virtual terminal. Press Ctrl+Alt+F7 to return to your X-Windows session.

https://fedorahosted.org/liberation-fonts/

Typographic Conventions

vii

The first sentence highlights the particular key cap to press. The second highlights two sets of three key caps, each set pressed simultaneously.

If source code is discussed, class names, methods, functions, variable names and returned values mentioned within a paragraph will be presented as above, in Mono-spaced Bold. For example:

File-related classes include filesystem for file systems, file for files, and dir for directories. Each class has its own associated set of permissions.

Proportional Bold

This denotes words or phrases encountered on a system, including application names; dialogue box text; labelled buttons; check-box and radio button labels; menu titles and sub-menu titles. For example:

Choose System > Preferences > Mouse from the main menu bar to launch Mouse

Preferences. In the Buttons tab, click the Left-handed mouse check box and click Close to switch the primary mouse button from the left to the right (making the mouse

suitable for use in the left hand).

To insert a special character into a gedit file, choose Applications > Accessories

> Character Map from the main menu bar. Next, choose Search > Find… from the Character Map menu bar, type the name of the character in the Search field and

click Next. The character you sought will be highlighted in the Character Table. Double-click this highlighted character to place it in the Text to copy field and then click the Copy button. Now switch back to your document and choose Edit > Paste from the gedit menu bar.

The above text includes application names; system-wide menu names and items; application-specific menu names; and buttons and text found within a GUI interface, all presented in Proportional Bold and all distinguishable by context.

Note the > shorthand used to indicate traversal through a menu and its sub-menus. This is to avoid the difficult-to-follow 'Select Mouse from the Preferences sub-menu in the System menu of the main menu bar' approach.

Mono-spaced Bold Italic or Proportional Bold Italic

Whether Mono-spaced Bold or Proportional Bold, the addition of Italics indicates replaceable or variable text. Italics denotes text you do not input literally or displayed text that changes depending on circumstance. For example:

To connect to a remote machine using ssh, type ssh username@domain.name at a shell prompt. If the remote machine is example.com and your username on that machine is john, type ssh john@example.com.

The mount -o remount file-system command remounts the named file system. For example, to remount the /home file system, the command is mount -o remount /home.

To see the version of a currently installed package, use the rpm -q package command. It will return a result as follows: package-version-release.

Note the words in bold italics above — username, domain.name, file-system, package, version and release. Each word is a placeholder, either for text you enter when issuing a command or for text displayed by the system.

Introduction

viii

Aside from standard usage for presenting the title of a work, italics denotes the first use of a new and important term. For example:

When the Apache HTTP Server accepts requests, it dispatches child processes or threads to handle them. This group of child processes or threads is known as a server-pool. Under Apache HTTP Server 2.0, the responsibility for creating and maintaining these server-pools has been abstracted to a group of modules called Multi-Processing Modules (MPMs). Unlike other modules, only one module from the MPM group can be loaded by the Apache HTTP Server.

1.2. Pull-quote Conventions

Two, commonly multi-line, data types are set off visually from the surrounding text.

Output sent to a terminal is set in Mono-spaced Roman and presented thus:

books Desktop documentation drafts mss photos stuff svn books_tests Desktop1 downloads images notes scripts svgs

Source-code listings are also set in Mono-spaced Roman but are presented and highlighted as follows:

package org.jboss.book.jca.ex1;

import javax.naming.InitialContext;

public class ExClient { public static void main(String args[]) throws Exception { InitialContext iniCtx = new InitialContext(); Object ref = iniCtx.lookup("EchoBean"); EchoHome home = (EchoHome) ref; Echo echo = home.create();

System.out.println("Created Echo");

System.out.println("Echo.echo('Hello') = " + echo.echo("Hello")); }

}

1.3. Notes and Warnings

Finally, we use three visual styles to draw attention to information that might otherwise be overlooked.

Feedback

Note

A note is a tip or shortcut or alternative approach to the task at hand. Ignoring a note should have no negative consequences, but you might miss out on a trick that makes your life easier.

Important

Important boxes detail things that are easily missed: configuration changes that only apply to the current session, or services that need restarting before an update will apply. Ignoring Important boxes won't cause data loss but may cause irritation and frustration.

Warning

A Warning should not be ignored. Ignoring warnings will most likely cause data loss.

2. Feedback

If you spot a typo, or if you have thought of a way to make this manual better, we would love to hear from you. Please submit a report in Bugzilla (http://bugzilla.redhat.com/bugzilla/) against the component rh-cs.

Be sure to mention the manual's identifier:

Cluster_Administration(EN)-4.8 (2009-5-13T12:45)

By mentioning this manual's identifier, we know exactly which version of the guide you have.

If you have a suggestion for improving the documentation, try to be as specific as possible. If you have found an error, please include the section number and some of the surrounding text so we can find it easily.

Chapter 1.

Red Hat Cluster Configuration and Management Overview

Red Hat Cluster allows you to connect a group of computers (called nodes or members) to work together as a cluster. You can use Red Hat Cluster to suit your clustering needs (for example, setting up a cluster for sharing files on a GFS file system or setting up service failover).

1.1. Configuration Basics

To set up a cluster, you must connect the nodes to certain cluster hardware and configure the nodes into the cluster environment. This chapter provides an overview of cluster configuration and management, and tools available for configuring and managing a Red Hat Cluster.

Configuring and managing a Red Hat Cluster consists of the following basic steps:

1. Setting up hardware. Refer to Section 1.1.1, “Setting Up Hardware”.

2. Installing Red Hat Cluster software. Refer to Section 1.1.2, “Installing Red Hat Cluster software”.

3. Configuring Red Hat Cluster Software. Refer to Section 1.1.3, “Configuring Red Hat Cluster

Software”.

1.1.1. Setting Up Hardware

Setting up hardware consists of connecting cluster nodes to other hardware required to run a Red Hat Cluster. The amount and type of hardware varies according to the purpose and availability requirements of the cluster. Typically, an enterprise-level cluster requires the following type of hardware (refer to Figure 1.1, “Red Hat Cluster Hardware Overview”).

• Cluster nodes — Computers that are capable of running Red Hat Enterprise Linux 4 software, with at least 1GB of RAM.

• Ethernet switch or hub for public network — This is required for client access to the cluster.

• Ethernet switch or hub for private network — This is required for communication among the cluster nodes and other cluster hardware such as network power switches and Fibre Channel switches.

• Network power switch — A network power switch is recommended to perform fencing in an enterprise-level cluster.

• Fibre Channel switch — A Fibre Channel switch provides access to Fibre Channel storage. Other options are available for storage according to the type of storage interface; for example, iSCSI or GNBD. A Fibre Channel switch can be configured to perform fencing.

• Storage — Some type of storage is required for a cluster. The type required depends on the purpose of the cluster.

For considerations about hardware and other cluster configuration concerns, refer to Chapter 2,

Before Configuring a Red Hat Cluster or check with an authorized Red Hat representative.

Chapter 1. Red Hat Cluster Configuration and Management Overview

Figure 1.1. Red Hat Cluster Hardware Overview

1.1.2. Installing Red Hat Cluster software

To install Red Hat Cluster software, you must have entitlements for the software. If you are using the Conga configuration GUI, you can let it install the cluster software. If you are using other tools to configure the cluster, secure and install the software as you would with Red Hat Enterprise Linux software.

1.1.3. Configuring Red Hat Cluster Software

Configuring Red Hat Cluster software consists of using configuration tools to specify the relationship among the cluster components. Figure 1.2, “Cluster Configuration Structure” shows an example of the hierarchical relationship among cluster nodes, high-availability services, and resources. The cluster nodes are connected to one or more fencing devices. Nodes can be grouped into a failover domain for a cluster service. The services comprise resources such as NFS exports, IP addresses, and shared GFS partitions.

Configuring Red Hat Cluster Software

Figure 1.2. Cluster Configuration Structure

The following cluster configuration tools are available with Red Hat Cluster:

• Conga — This is a comprehensive user interface for installing, configuring, and managing Red Hat clusters, computers, and storage attached to clusters and computers.

• system-config-cluster — This is a user interface for configuring and managing a Red Hat cluster.

• Command line tools — This is a set of command line tools for configuring and managing a Red Hat cluster.

A brief overview of each configuration tool is provided in the following sections:

• Section 1.2, “Conga”

• Section 1.3, “system-config-cluster Cluster Administration GUI”

• Section 1.4, “Command Line Administration Tools”

In addition, information about using Conga and system-config-cluster is provided in subsequent chapters of this document. Information about the command line tools is available in the man pages for the tools.

Chapter 1. Red Hat Cluster Configuration and Management Overview

1.2. Conga

Conga is an integrated set of software components that provides centralized configuration and

management of Red Hat clusters and storage. Conga provides the following major features:

• One Web interface for managing cluster and storage

• Automated Deployment of Cluster Data and Supporting Packages

• Easy Integration with Existing Clusters

• No Need to Re-Authenticate

• Integration of Cluster Status and Logs

• Fine-Grained Control over User Permissions

The primary components in Conga are luci and ricci, which are separately installable. luci is a server that runs on one computer and communicates with multiple clusters and computers via ricci. ricci is an agent that runs on each computer (either a cluster member or a standalone computer) managed by

Conga.

luci is accessible through a Web browser and provides three major functions that are accessible

through the following tabs:

• homebase — Provides tools for adding and deleting computers, adding and deleting users, and configuring user privileges. Only a system administrator is allowed to access this tab.

• cluster — Provides tools for creating and configuring clusters. Each instance of luci lists clusters that have been set up with that luci. A system administrator can administer all clusters listed on this tab. Other users can administer only clusters that the user has permission to manage (granted by an administrator).

• storage — Provides tools for remote administration of storage. With the tools on this tab, you can manage storage on computers whether they belong to a cluster or not.

To administer a cluster or storage, an administrator adds (or registers) a cluster or a computer to a luci server. When a cluster or a computer is registered with luci, the FQDN hostname or IP address of each computer is stored in a luci database.

You can populate the database of one luci instance from another luciinstance. That capability provides a means of replicating a luci server instance and provides an efficient upgrade and testing path. When you install an instance of luci, its database is empty. However, you can import part or all of a luci database from an existing luci server when deploying a new luci server.

Each luci instance has one user at initial installation — admin. Only the admin user may add systems to a luci server. Also, the admin user can create additional user accounts and determine which users are allowed to access clusters and computers registered in the luci database. It is possible to import users as a batch operation in a new luci server, just as it is possible to import clusters and computers.

When a computer is added to a luci server to be administered, authentication is done once. No authentication is necessary from then on (unless the certificate used is revoked by a CA). After that, you can remotely configure and manage clusters and storage through the luci user interface. luci and ricci communicate with each other via XML.

Conga

The following figures show sample displays of the three major luci tabs: homebase, cluster, and storage.

For more information about Conga, refer to Chapter 3, Configuring Red Hat Cluster With Conga,

Chapter 4, Managing Red Hat Cluster With Conga, and the online help available with the luci server.

Figure 1.3. luci homebase Tab

Figure 1.4. luci cluster Tab

Chapter 1. Red Hat Cluster Configuration and Management Overview

Figure 1.5. luci storage Tab

1.3. system-config-cluster Cluster Administration GUI

This section provides an overview of the cluster administration graphical user interface (GUI) available with Red Hat Cluster Suite — system-config-cluster. It is for use with the cluster infrastructure and the high-availability service management components. system-config-cluster consists of two major functions: the Cluster Configuration Tool and the Cluster Status Tool. The Cluster Configuration Tool provides the capability to create, edit, and propagate the cluster configuration file (/etc/cluster/cluster.conf). The Cluster Status Tool provides the capability to manage highavailability services. The following sections summarize those functions.

Note

While system-config-cluster provides several convenient tools for configuring and managing a Red Hat Cluster, the newer, more comprehensive tool, Conga, provides more convenience and flexibility than system-config-cluster.

Cluster Configuration Tool

1.3.1. Cluster Configuration Tool

You can access the Cluster Configuration Tool (Figure 1.6, “Cluster Configuration Tool”) through the Cluster Configuration tab in the Cluster Administration GUI.

Figure 1.6. Cluster Configuration Tool

The Cluster Configuration Tool represents cluster configuration components in the configuration file (/etc/cluster/cluster.conf) with a hierarchical graphical display in the left panel. A triangle icon to the left of a component name indicates that the component has one or more subordinate components assigned to it. Clicking the triangle icon expands and collapses the portion of the tree below a component. The components displayed in the GUI are summarized as follows:

• Cluster Nodes — Displays cluster nodes. Nodes are represented by name as subordinate elements under Cluster Nodes. Using configuration buttons at the bottom of the right frame (below Properties), you can add nodes, delete nodes, edit node properties, and configure fencing methods for each node.

Chapter 1. Red Hat Cluster Configuration and Management Overview

• Fence Devices — Displays fence devices. Fence devices are represented as subordinate elements under Fence Devices. Using configuration buttons at the bottom of the right frame (below Properties), you can add fence devices, delete fence devices, and edit fence-device properties. Fence devices must be defined before you can configure fencing (with the Manage Fencing For This Node button) for each node.

• Managed Resources — Displays failover domains, resources, and services.

• Failover Domains — For configuring one or more subsets of cluster nodes used to run a high-

availability service in the event of a node failure. Failover domains are represented as subordinate elements under Failover Domains. Using configuration buttons at the bottom of the right frame (below Properties), you can create failover domains (when Failover Domains is selected) or edit failover domain properties (when a failover domain is selected).

• Resources — For configuring shared resources to be used by high-availability services. Shared

resources consist of file systems, IP addresses, NFS mounts and exports, and user-created scripts that are available to any high-availability service in the cluster. Resources are represented as subordinate elements under Resources. Using configuration buttons at the bottom of the right frame (below Properties), you can create resources (when Resources is selected) or edit resource properties (when a resource is selected).

Note

The Cluster Configuration Tool provides the capability to configure private resources, also. A private resource is a resource that is configured for use with only one service. You can configure a private resource within a Service component in the GUI.

• Services — For creating and configuring high-availability services. A service is configured by

assigning resources (shared or private), assigning a failover domain, and defining a recovery policy for the service. Services are represented as subordinate elements under Services. Using configuration buttons at the bottom of the right frame (below Properties), you can create services (when Services is selected) or edit service properties (when a service is selected).

1.3.2. Cluster Status Tool

You can access the Cluster Status Tool (Figure 1.7, “Cluster Status Tool”) through the Cluster Management tab in Cluster Administration GUI.

Command Line Administration Tools

Figure 1.7. Cluster Status Tool

The nodes and services displayed in the Cluster Status Tool are determined by the cluster configuration file (/etc/cluster/cluster.conf). You can use the Cluster Status Tool to enable, disable, restart, or relocate a high-availability service.

1.4. Command Line Administration Tools

In addition to Conga and the system-config-cluster Cluster Administration GUI, command line tools are available for administering the cluster infrastructure and the high-availability service management components. The command line tools are used by the Cluster Administration GUI and init scripts supplied by Red Hat. Table 1.1, “Command Line Tools” summarizes the command line tools.

Chapter 1. Red Hat Cluster Configuration and Management Overview

Command Line Tool

Used With Purpose

ccs_tool

— Cluster Configuration System Tool

Cluster Infrastructure

ccs_tool is a program for making online updates to the cluster configuration file. It provides the capability to create and modify cluster infrastructure components (for example, creating a cluster, adding and removing a node). For more information about this tool, refer to the ccs_tool(8) man page.

cman_tool

— Cluster Management Tool

Cluster Infrastructure

cman_tool is a program that manages the CMAN cluster manager. It provides the capability to join a cluster, leave a cluster, kill a node, or change the expected quorum votes of a node in a cluster. cman_tool is available with DLM clusters only. For more information about this tool, refer to the cman_tool(8) man page.

gulm_tool

— Cluster Management Tool

Cluster Infrastructure

gulm_tool is a program used to manage GULM. It provides an interface to lock_gulmd, the GULM lock manager. gulm_tool is available with GULM clusters only. For more information about this tool, refer to the gulm_tool(8) man page.

fence_tool — Fence Tool

Cluster Infrastructure

fence_tool is a program used to join or leave the default fence domain. Specifically, it starts the fence daemon (fenced) to join the domain and kills fenced to leave the domain. fence_tool is available with DLM clusters only. For more information about this tool, refer to the fence_tool(8) man page.

clustat — Cluster Status Utility

High-availability Service Management Components

The clustat command displays the status of the cluster. It shows membership information, quorum view, and the state of all configured user services. For more information about this tool, refer to the clustat(8) man page.

clusvcadm

— Cluster User Service Administration Utility

High-availability Service Management Components

The clusvcadm command allows you to enable, disable, relocate, and restart high-availability services in a cluster. For more information about this tool, refer to the clusvcadm(8) man page.

Table 1.1. Command Line Tools

Chapter 2.

Before Configuring a Red Hat Cluster

This chapter describes tasks to perform and considerations to make before installing and configuring a Red Hat Cluster, and consists of the following sections:

• Section 2.1, “Compatible Hardware”

• Section 2.2, “Enabling IP Ports”

• Section 2.3, “Configuring ACPI For Use with Integrated Fence Devices”

• Section 2.4, “Configuring max_luns”

• Section 2.5, “Considerations for Using Quorum Disk”

• Section 2.7, “Considerations for Using Conga”

• Section 2.8, “General Configuration Considerations”

2.1. Compatible Hardware

Before configuring Red Hat Cluster software, make sure that your cluster uses appropriate hardware (for example, supported fence devices, storage devices, and Fibre Channel switches). Refer to the hardware configuration guidelines at http://www.redhat.com/cluster_suite/hardware/ for the most current hardware compatibility information.

2.2. Enabling IP Ports

Before deploying a Red Hat Cluster, you must enable certain IP ports on the cluster nodes and on computers that run luci (the Conga user interface server). The following sections specify the IP ports to be enabled and provide examples of iptables rules for enabling the ports:

• Section 2.2.1, “Enabling IP Ports on Cluster Nodes”

• Section 2.2.2, “Enabling IP Ports on Computers That Run luci”

• Section 2.2.3, “Examples of iptables Rules”

2.2.1. Enabling IP Ports on Cluster Nodes

To allow Red Hat Cluster nodes to communicate with each other, you must enable the IP ports assigned to certain Red Hat Cluster components. Table 2.1, “Enabled IP Ports on Red Hat Cluster

Nodes” lists the IP port numbers, their respective protocols, the components to which the port

numbers are assigned, and references to iptables rule examples. At each cluster node, enable IP ports according to Table 2.1, “Enabled IP Ports on Red Hat Cluster Nodes”. (All examples are in

Section 2.2.3, “Examples of iptables Rules”.)

IP Port Number

Protocol Component Reference to Example of

iptables Rules

6809 UDP cman (Cluster Manager), for use

in clusters with Distributed Lock Manager (DLM) selected

Example 2.1, “Port 6809: cman”

Chapter 2. Before Configuring a Red Hat Cluster

IP Port Number

Protocol Component Reference to Example of

iptables Rules

11111 TCP ricci (part of Conga remote

agent)

Example 2.3, “Port 11111: ricci (Cluster Node and Computer Running luci)”

14567 TCP gnbd (Global Network Block

Device)

Example 2.4, “Port 14567: gnbd”

16851 TCP modclusterd (part of Conga

remote agent)

Example 2.5, “Port 16851: modclusterd”

21064 TCP dlm (Distributed Lock Manager), for

use in clusters with Distributed Lock Manager (DLM) selected

Example 2.6, “Port 21064: dlm”

40040, 40042, 41040

TCP lock_gulmd (GULM daemon), for

use in clusters with Grand Unified Lock Manager (GULM) selected

Example 2.7, “Ports 40040, 40042, 41040: lock_gulmd”

41966, 41967, 41968, 41969

TCP rgmanager (high-availability

service management)

Example 2.8, “Ports 41966, 41967, 41968, 41969: rgmanager”

50006, 50008, 50009

TCP ccsd (Cluster Configuration

System daemon)

Example 2.9, “Ports 50006, 50008, 50009: ccsd (TCP)”

50007 UDP ccsd (Cluster Configuration

System daemon)

Example 2.10, “Port 50007: ccsd (UDP)”

Table 2.1. Enabled IP Ports on Red Hat Cluster Nodes

2.2.2. Enabling IP Ports on Computers That Run luci

To allow client computers to communicate with a computer that runs luci (the Conga user interface server), and to allow a computer that runs luci to communicate with ricci in the cluster nodes, you must enable the IP ports assigned to luci and ricci. Table 2.2, “Enabled IP Ports on a Computer

That Runs luci” lists the IP port numbers, their respective protocols, the components to which the port

numbers are assigned, and references to iptables rule examples. At each computer that runs luci, enable IP ports according to Table 2.1, “Enabled IP Ports on Red Hat Cluster Nodes”. (All examples are in Section 2.2.3, “Examples of iptables Rules”.)

Note

If a cluster node is running luci, port 11111 should already have been enabled.

IP Port Number

Protocol Component Reference to Example of

iptables Rules

8084 TCP luci (Conga user interface server) Example 2.2, “Port 8084: luci

(Cluster Node or Computer Running luci)”

Examples of iptables Rules

IP Port Number

Protocol Component Reference to Example of

iptables Rules

11111 TCP ricci (Conga remote agent) Example 2.3, “Port 11111: ricci

(Cluster Node and Computer Running luci)”

Table 2.2. Enabled IP Ports on a Computer That Runs luci

2.2.3. Examples of iptables Rules

This section provides iptables rule examples for enabling IP ports on Red Hat Cluster nodes and computers that run luci. The examples enable IP ports for a computer having an IP address of

10.10.10.200, using a subnet mask of 10.10.10.0/24.

Note

Examples are for cluster nodes unless otherwise noted in the example titles.

-A INPUT -i 10.10.10.200 -m state --state NEW -p udp -s 10.10.10.0/24 -d

10.10.10.0/24 --dport 6809 -j ACCEPT

Example 2.1. Port 6809: cman