HP Q1538-90925 User Manual

HP Ultrium tape drives technical reference manual

Generation 3 drives

volume 5: UNIX configuration guide

Part number: Q1538–90925 Volume 5 Edition 6.4, May 2006

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Legal and notice information

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.

This document contains proprietary information, which is protected by copyright. No part of this document may be photocopied, reproduced, or translated into another language without the prior written consent of Hewlett-Packard. The information is provided “as is” without warranty of any kind and is subject to change without notice. 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.

Revision history

Version Date Changes

Edition 6 September 2004 Generation 3 SCSI and FC drive version

Edition 6.2 May 2005 Reformatted and updated

Edition 6.3 November 2005 Small change to IBM configuration procedure

Edition 6.4 May 2006 Modifications to the HP-UX chapter

This document is frequently revised and updated. To find out if there is a later version, please ask your HP OEM Representative.

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The following applications are suitable for use within an Enterprise environment and have been tested with Ultrium drives. They use the operating system’s standard, built-in device drivers, as described in this manual. For further information about optimizing performance and making full use of the drive’s functions, contact the software manufacturer or HP.

HP Omniback Legato Networker yes yes yes yes Veritas NetBackup yes yes yes yes

1. Cell Manager is only available on HP-UX or Windows

2. Redhat Server only (not Caldera, SUSE, and so on)

1

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HP-UX AIX Sun, Solaris Linux

yes yes yes yes

2

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Introduction10

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2HP-UX systems

HP servers and workstations—HP-UX 11.x

NOTE: HP-UX 10.x is only supported by Generation 1 Ultrium drives.

Introduction

Before you install your tape drive log on to the HP web site, www.hp.com, and download the latest hardware enablement patch bundle for your operating system. This ensures that you will have the correct device driver for your tape drive.

Determining attached devices

After you have installed the new tape drive, you can check it has been attached successfully. From a shell window (hpterm/xterm), execute ioscan to display the list of attached devices.

# /sbin/ioscan -C tape -fn

The output should look similar to the following:

Class I H/W Path Driver S/W State H/W Type Description ================================================================================= bc 0 root CLAIMED BUS_NEXUS bc 1 8 bc CLAIMED BUS_NEXUS Psudo Bus Converter ba 0 8/0 GSCtoPCI CLAIMED BUS_NEXUS GSCtoPCI Bridge ext_bus 1 8/0/2/0 c720 CLAIMED INTERFACE SCSI C895 Ultra2 Wide LVD target 0 8/0/2/0.7 tgt CLAIMED DEVICE ctl 1 8/0/2/0.7.0 sctl CLAIMED DEVICE Initiator lan 0 8/0/20/0 btlan3 CLAIMED INTERFACE PCI(10110019) -- Built-in #1 ba 1 8/16 bus_adapter CLAIMED BUS_NEXUS Core I/O Adapter tty 0 8/16/4 asio0 CLAIMED INTERFACE Built-in RS-232C ext_bus 2 8/16/5 c720 CLAIMED INTERFACE Built-in SCSI target 1 8/16/5.5 tgt CLAIMED DEVICE disk 0 8/16/5.5.0 sdisk CLAIMED DEVICE SEAGATE ST34573N target 2 8/16/5.7 tgt CLAIMED DEVICE ctl 2 8/16/5.7.0 sctl CLAIMED DEVICE Initiator processor 0 62 processor CLAIMED PROCESSOR Processor memory 0 63 memory CLAIMED MEMORY Memory tape 4 2/0/1.5.0 stape CLAIMED DEVICE HP Ultrium 3-SCSI

NOTE: If you are installing the drive onto a Storage Area Network (SAN), the fibre channel/SCSI

bridge will also appear in the list of attached devices.

Adding stape and schgr (autoloader driver) to the kernel using sam

Run the `sam` utility from the command line. Sam runs as a mouse driven GUI (fig. 1) on a system with full graphics capability, or as a console text-based interface (fig. 2). If using the text-based interface, use the tab and arrow keys to navigate, and the return key to select.

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Figure 1 SAM GUI

Figure 2 SAM text-based interface

For HP-UX 11.11 (11i version 1)

1. Enter sam at the command line.

2. Select the following:

Kernel Configuration Drivers

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3. Highlight the stape or schgr driver. If the driver has not been added to the kernel, both

Current State and Pending State will read “Out”.

4. Select the following:

Actions Add Driver to Kernel

The Pending State will now read “In”.

5. To add the new driver to the kernel, select:

Actions Create a New Kernel

The stape or schgr driver is added to the kernel.

6. Reboot the system.

For HP-UX 11.23 (11i version 2)

1. Enter sam at the command line.

2. Select the following:

Kernel Configuration Kernel Configuration Modules

3. Highlight the stape or schgr driver. If the driver has not been added to the kernel, both

Current State and Planned State will read “unused”.

4. Type “m” to modify the stape driver and “s” to set it to “static”. The Planned State will now read

“static”.

5. Change schgr to “static” if you are going to attach an autoloader.

6. The stape and schgr drivers are now added to the kernel.

7. Reboot the system.

Add device files using sam

This is the recommended and simplest way to create device files. To add devices, proceed as follows:

1. # sam

This will bring up the graphical user interface for the utility.

2. Select the following:

Peripheral Devices Tape Drives

sam will then scan the system for any tape drives connected.

When a HP Ultrium Generation 3 drive is found, for example, it will be displayed as:

Hardware Path Driver Description =========================================================== 8/0/2/0.3.0 stape HP Ultrium 3-SCSI

3. Highlight the drive and select the following from the tool bar:

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Actions Create Device Files Create Default Device Files

This will create default device files for the drive. To view the device files that have been created, select:

Actions Create Device Files Show Device Files

4. When you have exited sam, run ioscan to see the tape drive:

%/sbin/ioscan -C tape -fn

All default device files displayed have compression enabled.

NOTE: HP recommends the ‘Berkeley’ device files of most applications:

cXtYdZBESTnb = Berkeley, no rewind, best available density cXtYdZBESTb = Berkeley, with rewind, best available density

where:

X = card number Y = target number Z = LUN number

What next?

Once device files have been created, you should confirm that your new tape drive is working properly. Chapter 7 on page 27 provides instructions on backing up and restoring a sample file to test your installation.

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3 HP alpha UNIX

HP alpha UNIX 5.x

1. Add the following entry to your /dev/ddr.dbase file:

SCSIDEVICE Type = tape Name = “HP” “Ultrium” # PARAMETERS: TypeSubClass = lto # Linear Tape Open BlockSize = 262144 TagQueueDepth = 0 MaxTransferSize = 0xffffff # 16Mb - 1 ReadyTimeSeconds = 120 # Seconds SyncTransfers = enabled WideTransfers = enabled InquiryLength = 0x20 DENSITY: DensityNumber = 0,1,2,3,4,5,6,7 OneFileMarkOnClose = yes DensityCode = 0x44 Blocking = 0 CompressionCode = 1 Buffered = 1 Speed = 0 MODESELECT: ModeSelectNumber = 0 SavePage = No PageFormat = scsi2 BlockDescriptor = yes TransferLength = 16 Hdr.Tape.BufferMode = 0x1 Hdr.MediumType = 0 Data.UBYTE[0] = 0x3D # Vendor Unique Page Code 3D Data.UBYTE[1] = 0x02 Data.UBYTE[2] = 0x01 Data.UBYTE[3] = 0x00

2. Rebuild the kernel by running /sbin/ddr_config, then reboot the system with the tape drive

attached. Device files for the Ultrium drive will be generated in /dev/tape and /dev/ntape when you reboot.

3. The names of the device files can be interpreted as follows:

Devices in the /dev/ntape perform rewind on close.

directory are “no-rewind” devices. Those in /dev/tape will

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The device files then have the syntax: tapeX_dn For example, /dev/ntape/tape66_d1

number 1. Since all density numbers have the same parameters it does not matter which density number file is used.

What next?

Once device files have been created, you should confirm that your new tape drive is working properly. Chapter 7 on page 27 provides instructions on backing up and restoring a sample file to test your installation.

is a device file for device 66, no-rewind using density

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4IBM (AIX)

Determining the SCSI ID

Before you configure your system to support Ultrium drives, determine which SCSI ID to use. IDs must be unique for each device attached to the SCSI bus. To list existing devices, use the following command:

% lsdev -C |grep SCSI

This produces output similar to:

scsi0 Available 00-00-0S Standard SCSI I/O Controller hdisk0 Available 10-60-00-0,0 16 Bit LVD SCSI Disk Drive rmt1 Defined 00-00-0S-2,0 Other SCSI Tape Drive

The SCSI ID is in the series 00-00-0S-X,0, where X is the SCSI ID. Review the list of existing SCSI IDs and choose an available ID to assign to the new tape drive.

Configuring the device files

To install an HP Ultrium drive on an IBM workstation, create the appropriate device files for the drive.

NOTE: Do not choose the smit option of “4mm2gb” as the Tape Device Type. This is reserved for

Connor drives. If you use it with HP drives, you will get the error “Device to be configured does not match the physical device at the specified connection location”.

To change to variable block mode, use the following procedure:

1. If you are using a graphics terminal running X-Windows, at a Windows terminal, type:

smit tape If you are using a non-graphics terminal, at the command line type:

% smit -C tape

2. If no device has been configured at this address before, select “add a tape drive” to set up

the address. From the pop-up window, select “ost” or “Other SCSI tape drive” as the tape drive you wish to change and choose connection addresses as appropriate.

3. Set maximum delay for the READ/WRITE command=1200.

4. Change the block size field to 0, and click on the “DO” button or press [Enter] to apply the

change.

HP Ultrium drives will work with tar, cpio, backup, restore and dd. For systems other than the 43P, the drive is also boot-capable, provided a boot tape is generated using mkszfile and mksysb.

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Once device files have been created, you should confirm that your new tape drive is working properly. Chapter 7 on page 27 provides instructions on backing up and restoring a sample file to test your installation.

Device filenames under AIX

Use device filenames as listed below for the combination of Rewind on Close, Retension on Open, and Compression that you want:

Filename Rewind on Close Retension on Open Compression

/dev/rmtn Yes No enabled /dev/rmtn.1 No No enabled /dev/rmtn.2 Yes Yes enabled /dev/rmtn.3 No Yes enabled /dev/rmtn.4 Yes No disabled /dev/rmtn.5 No No disabled /dev/rmtn.6 Yes Yes disabled /dev/rmtn.7 No Yes disabled

The n in the filename is the instance number assigned to the drive by the operating system, where 0 is the first device, 1 is the second and so on.

Rewind on Close Normally, the drive repositions the tape to BOT (Beginning of Tape) when the

device file is closed. Using the no rewind option is useful when creating and reading tapes that contain multiple files.

Retension on Open Retensioning consists of winding to EOT (End of Tape) and then rewinding to

BOT, in order to reduce errors. If this option is selected, the tape is positioned at BOT as part of the open process.

Compression Compression can be disabled or enabled.

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5Linux

Determining the SCSI ID (Linux)

Look at the output of dmesg to find out what SCSI channel number is used for each connection.

To find out the SCSI IDs in use on each channel, type:

cat /proc/scsi/scsi

This will produce output similar to the following for each device:

Attached Devices Host: SCSI0 Channel: 00 Id:00 Lun:00 Vendor: HP Model -----------Type: Direct-Access ANSI SCSI Revision 02

Look at the ID information to establish which IDs are in use.

Configuring on Linux systems

No changes are needed to support Ultrium on Linux platforms, however you should ensure that you have the relevant drivers loaded.

To see the device drivers loaded currently, execute lsmod. This will give output similar to:

Module Size Used by sgm 4376 1 ide-scsi 7200 0 lockd 30792 1 sunrpc 53316 1 st 24656 0 sym53c8xx 52096 1 aic7xxx 136184 2

The lines of interest here are:

st The tape driver. Its presence shows that the tape driver is loaded.

sym53c8xx The SCSI chipset driver for the LSI Logic family of HBAs (amongst others).

aic7xxx The SCSI chipset driver for the Adaptec 7xxx chipset family (such as Adaptec

29160LP).

Latest SCSI controller drivers for Linux are available from the manufacturer’s web site.

In order to communicate with a tape device, the operating system needs to have drivers for the tape and the underlying transport mechanism (the host bus adaptor) loaded. Ensure that both are available as either loadable modules (for example, usable with insmod and visible with lsmod) or are statically built into your kernel.

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NOTE: To add drivers to the statically built kernel you need the Linux source code available on disk

and knowledge of how to use the kernel building tools that ship with various Linux distributions. This should not be attempted by novice users.

In order to determine if the drive has been detected by the tape driver at module load time, execute:

dmesg | grep "st"

This should find a number of lines. One should look like:

Detected SCSI tape st0 at scsi1, channel 0, id 5, lun 0

To load the tape driver module if it is not loaded as above, execute:

insmod st

to load it. This should happen naturally if your system is rebooted after attaching the drive.

When the ST driver module has been added, a list of tape device files will be created automatically. They reside in the /dev/ directory and have the syntax:

/dev/stp or dev/nstp

where:

Instance number of the device file (if only one drive is connected to the system, this will be 0)

p n Indicates this is a no-rewind driver.

To enable large transfers under Linux (>64 KB per write), edit the file

/usr/src/linux/drivers/scsi/st_options.h and change the definition of ST_BUFFER_BLOCKS.

If you want requests to space to end of data (EOD) to be faster, you should also enable ST_FAST_MTEOM in the same file. After changing this file, rebuild the modules and install the new binary. At the very least, this requires:

make modules make modules_install

from the /usr/src/linux directory. See your kernel documentation.

Using the seek and tell features of mt

To use the seek and tell features of mt, you must tell the st driver that HP Ultrium drives use logical block addressing:

mt -f <device file> stsetoptions scsi2logical

where /dev/stp is the device file.

Note however that this information is not preserved across reboots, so you need to execute this command each time the system comes up. The stinit utility offers a convenient way of handling this; see the relevant man page for more information. If you use this approach, set the manufacturer parameter to HP and the model to “Ultrium 3-SCSI”.

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What next?

Once device files have been created, you should confirm that your new tape drive is working properly. Chapter 7 on page 27 provides instructions on backing up and restoring a sample file to test your installation.

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Linux22

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6 Sun Systems, Solaris 8, 9, 10

Determining the SCSI ID

Before you configure your system to support an HP Ultrium drive, determine which SCSI ID to use. IDs must be unique for each device on attached to the SCSI bus.

1. Use the modinfo command to identify SCSI controller drivers installed on the system:

% modinfo | grep "HBA Driver"

This produces output similar to the following:

106 780a0000 102b3 50 1 glm (GLM SCSI HBA Driver) 110 780b4000 1272c 228 1 qus (isp10160 HBA Driver)

For the adapter to which the new tape drive is attached, you need to determine what SCSI IDs are already used.

2. Determine the SCSI IDs of existing devices attached to the SCSI controller:

For all adapters:

% dmesg | egrep ".*xxx.*target" | sort | uniq

where xxx = the type of adapter (esp, glm, fas, qus or isp), as appropriate. For example, for an ESP-based adapter:

% dmesg | egrep ".*esp.*target" | sort | uniq

This produces a list similar to:

sd0 at esp0: target 0 lun 0 sd6 at esp0: target 6 lun 0

This indicates that SCSI IDs 0 and 6 are used for existing devices. SCSI ID 7 is generally used for the adapter itself. Here, you would choose a SCSI ID from 1 to 5 for the new tape drive.

Configuring the Device Files

Determine the device file by typing:

% ls -l /dev/rmt/*m | grep "st@X"

where X is the SCSI ID. Identify the line for the tape drive. For example, if the drive was at SCSI ID 2, look for the line containing “st@2,0”. This might be as follows (but on a single line):

lrwxrwxrwx 1 root root 63 Mar 1 00:00 /dev/rmt/0m ../../devices/sbus@1f,0/espdma@e,8400000/esp@e, 8800000/st@2,0:m

Here you could use /dev/rmt/0m (shown underlined above) as the device file.

For optimal performance, ensure that you have the following minimum patch number:

Minimum patch

Solaris 8 108725-18 Solaris 9 113277-27

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If for some reason you cannot upgrade to the minimum patch level, you can make the following file modifications to enhance performance:

1. In the file /kernel/drv/st.conf, after these lines:

#ident "@(#)st.conf 1.6 93/05/03 SMI"

Sun Microsystems, Inc.

add the following depending on which version of operating system you are installing (there are

6 significant spaces between HP and Ultrium in line 2):

for Solaris 8 without st patch:

tape-config-list =

"HP Ultrium 3","HP Ultrium LTO 3","HP_LTO_GEN_3"; HP_LTO_GEN_3 = 1,0x36,0,0xd639,4,0x44,0x44,0x44,0x44,3;

name="st" class="scsi"

target=X lun=0;

where X is the SCSI target address of the device you have attached.

for Solaris 9 and 10 (and 8 with st patch):

tape-config-list =

"HP Ultrium 3","HP Ultrium LTO 3","HP_LTO_GEN_3";

HP_LTO_GEN_3 = 2,0x3B,0,0x18659,4,0x44,0x44,0x44,0x44,3,60,1200, 600,1200,600,600,18000; name="st" class="scsi"

target=X lun=0;

where X is the SCSI target address of the device you have attached. See “HP-Data Values” on page 25 below for the values of the parameters in these lines.

2. If you are replacing an existing tape device on the same SCSI ID, remove the contents of the

/dev/rmt directory as follows:

% cd /dev/rmt % rm *

3. Do a reconfigure boot:

% cd / % touch /reconfigure % sync;halt

4. When the system is down, reboot:

% boot -r

Make sure you include the -r switch, so that the device directory is reconfigured using the new data.

5. You should now be able to use the drive.

•Use /dev/rmt/Xcb if you require a compression rewind device file, where X is the relevant device address.

•Use /dev/rmt/Xcbn when you require a compression non-rewind device.

Once the device files have been created, you should confirm that your new tape drive is working properly. Chapter 7 on page 27 provides instructions on backing up and restoring a sample file to test your installation.

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HP-Data Values

The values for HP_LTO_GEN_n and name, which provide normal LTO mode, have the following meanings:

The syntax for HP_LTO_GEN_n on Solaris 9 is:

<drive type> = <version>, <type>, <bsize>, <options>, <no. of densities>,

where:

Parameter Value Meaning

<version> 1 or 2 Indicates the format of the following parameters.

<type> 0x36 or

<bsize> 0 Indicates variable block size.

<options> 0xd639 or

0x3B

0x18659

The value for an Ultrium drive in /usr/include/sys/mtio.h. For Solaris 8, 0x36 indicates a type of MT_ISOTHER. Later versions of Solaris support the value 0x3B which indicates a type of MT_LTO.

This value is derived from constants provided in /usr/include/sys/scsi/targets/stdef.h. The value determines which operations the driver can perform with the attached device by using a unique value for each feature and then adding them together to form the options value. Supported features will vary with OS revision, and may include the following:

0x001 Device supports variable length records. 0x008 Device can backspace over files (as in the ‘mt bsf’ option). 0x010 Device supports backspace record (as in ‘mt bsr’). 0x020 Device requires a long time-out period for erase functions.

0x040 Device will automatically determine the tape density. 0x0200 Device knows when end of data has been reached. 0x0400 Device driver is unloadable. 0x1000 Time-outs five times longer than normal. 0x4000 Driver buffers write requests and pre-acknowledges success

to application.

0x8000 Variable record size not limited to 64 KB. 0x10000 Device determines which of the two mode pages the device

supports for selecting or deselecting compression.

So 0xd639 indicates variable record length, bsf and bsr enabled, long timeouts for erase, EOD recognition, Unloadable device driver, 5 x longer timeouts, buffer writes and pre-acknowledge sucess, variable records not limited to 64 KB, auto-density over-ride and

MODE SELECT

compression.

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Parameter Value Meaning

<no. of

4 There are four densities following in the parameter list.

densities> <density n> 0x00 Creates a device file with compression disabled. <density 3> 0x44 The density code for data compression enabled by default.

<default

3 Density 3 (0x44) is the default for Generation 3 drives.

density>

<X timeout> All timeouts are in seconds

Values for the parameters for name are as follows:

Parameter Value Meaning

target XX specifies the SCSI ID (target) of the device.

lun 0 Specifies the LUN for the device.

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7 Verifying the Installation

Verifying the Installation of the Drive (UNIX)

As part of the installation process, you will have installed the appropriate device driver for your UNIX system, and created device files to communicate with the tape drive.

This section describes how you can verify the installation has been performed correctly.

In outline, the procedure is as follows:

1. Check the tape drive responds to a rewind command.

2. Write test data to a tape.

3. Read the test data from the tape.

4. Compare the data read from the tape with the original data on disk.

To verify the installation:

1. Test the SCSI connection to the tape drive by performing a rewind:

a. If there is a tape cartridge already in the drive, remove it. b. Insert a tape cartridge. c. Rewind the tape using the command line:

% mt -f <device file> rewind

For example, on HP-UX:

% mt -f /dev/rmt/0mnb rewind

If the command completes successfully, there will be no feedback. If it fails, you will see an error message on the console. The hardware installation may be faulty. Check the troubleshooting section of the User’s Guide for help in identifying the problem.

2. Write a sample file to tape, using ‘tar’:

% cd / % tar cvf <device file> <file>

The options to tar have the following meanings:

c Create a new archive (backup file) on the device. v Operate in verbose mode. f Specify the device file explicitly.

The arguments follow the cvf options in the command line. Their values depend on the operating system; suggested values are given the appropriate operating system chapter.The arguments are as follows:

<device file> The name of the device file for the drive.

Example: /dev/rmt/0m

<file> The name of the file to archive, prefixed with ‘./’.

Example: ./stand/vmunix

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NOTE: Make sure you prefix the file name with ‘.’ when you back it up to tape. If you do not, the

restore operation in step 3 will overwrite the original copy on disk.

3. Read the file back from tape:

4. Compare the original with this retrieved file:

Example

Suppose you are verifying the installation of an HP Ultrium tape drive on an HP-UX 11.X system. The procedure would be as follows.:

1. Change directory to root:

2. Back up /stand/vmunix to tape:

3. Change to the temporary directory:

4. Extract the file from the tape:

5. Compare the original with the restored version:

% cd /tmp % tar xvf <device file>

The ‘x’ option to tar here means “extract from the archive”. Use the same value for the <device file> argument as in step 2.

% cmp <original file> /tmp/<retrieved file>

This compares the files byte by byte. If they are the same, there should be no output, and this verifies that the installation is correct. The arguments are:

<original file> The name of the original file, prefixed with ‘/’.

Example: /stand/vmunix

<retrieved file> The name of the file retrieved from the archive.

Example: stand/vmunix

% cd /

% tar cvf /dev/rmt/0m ./stand/vmunix

Note the prefix of ‘.’ to the filename.

% cd /tmp

% tar xvf /dev/rmt/0m

% cmp /stand/vmunix /tmp/stand/vmunix

Note that the original filename is not prefixed with ‘.’.

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Glossary

AT&T mode Berkeley and AT&T functional modes differ in “read-only” close functionality. In AT&T

mode, a device close operation will cause the tape to be repositioned just after next filemark on the tape (the start of the next file).

Berkeley mode Berkeley and AT&T functional modes differ in “read-only” close functionality. In

Berkeley mode the tape position will remain unchanged by a device close operation.

BOT Beginning Of Tape. The first point on the tape that can be accessed by the drive.

buffered mode A mode of data transfer in write operations that facilitates tape streaming. It is selected

by setting the Buffered Mode Field to 1 in the SCSI header.

compression A procedure in which data is transformed by the removal of redundant information in

order to reduce the number of bits required to represent the data. This is basically done by representing strings of bytes with codewords.

In Ultrium drives, the data is compressed using the LTO-DC compression format which is based on ALDC (licensed from Stac/IBM) with two enhancements. One limits the increase in size of data that cannot be compressed that ALDC produces. The other is the use of embedded codewords.

data transfer phase On a SCSI bus, devices put in requests to be able to transfer information. Once a

device is granted its request, it and the target to which it wants to send information can transfer the data using one of three protocols (assuming both devices support them): asynchronous, synchronous, and wide.

In asynchronous transfers, the target controls the flow of data. The initiator can only send data when the target has acknowledged receipt of the previous packet. All SCSI devices must support asynchronous transfer.

In synchronous data transfer, the initiator and target work in synchronization, allowing transmission of a packet of data to start before acknowledgment of the previous transmission.

In wide (16-bit) data transfer, two bytes are transferred at the same time instead of a single byte.

HP Ultrium drives support asynchronous, synchronous and narrow (8-bit) wide transfers.

MODE SELECT Parameter List

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fibre channel Fibre Channel provides an inexpensive yet expendable means of quickly transferring

data between workstations, mainframes, supercomputers, desktop computers, storage devices, displays and other peripherals. Although it is called Fibre Channel, its architecture represents neither a channel nor a real network topology. It allows for an active intelligent interconnection scheme, called a fabric, to connect devices. All a Fibre Channel port has to do is to manage a simple point-to-point connection between itself and the fabric.

Several common ULPs (Upper Level Protocols) including IP and SCSI can run on Fibre Channel, merging high-speed I/O and network functionality in a single connectivity technology.

filemark A mark written by the host to the tape that can be searched for, often using the drive’s

fast-search capability. It does not necessarily separate files. It is up to the host to assign a meaning to the mark.

immediate mode A mode of responding to SCSI commands where the drive or other peripheral does not

wait until the command has finished before returning status information back to the host. For writing filemarks, Immediate mode can significantly improve the performance of systems that do not set the Immediate bit when sending a SCSI

WRITE FILEMARKS

command. On the other hand, data is not flushed to tape in response to a filemark command.

infinite flush By default, the buffer in the drive is flushed every 5 seconds. Infinite flush avoids

frequent starting and stopping of the mechanism when using a very slow application. It also avoids losing capacity through the flushing of partly written groups. On the other hand, infinite flush means that data can remain in the buffer for very long periods of time, and could be lost in the event of a power failure.

LUN Logical Unit Number. A unique number by which a device is identified on the SCSI

bus. A tape drive has a fixed LUN of 0. In an autoloader, the changer mechanism is LUN1.

SAN Storage Area Network. A dedicated, high-speed network that establishes a direct

connection between storage elements and servers. The hardware that connects workstations and servers to storage devices in a SAN is referred to as a fabric. The SAN fabric enables any-server-to-any-storage device connectivity through the use of Fibre Channel switching technology.

SCSI Small Computer System Interface. A standard command specification and command

set that enables computers and peripherals to communicate with each other. HP’s Ultrium drives adhere to the SCSI-3 specification and support all features required by that standard.

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Single-Ended and Low Voltage Differential SCSI

These terms define how the signals are transmitted along the cable. With single-ended (SE) SCSI, each signal travels over a single wire and each signal’s

value is determined by comparing the signal to a paired ground wire. Signal quality tends to decrease over longer cable lengths or at increased signal speed.

With low voltage differential (LVD) signaling, signals travel along two wires and the difference in voltage between the wire pairs determines the signal value. This enables faster data rates and longer cabling with less susceptibility to noise than SE signaling and reduced power consumption.

Narrow and Wide, Fast, Ultra and Ultra2 SCSI

• Narrow SCSI devices can transfer data one byte at-a-time (and are sometimes

called “8-bit SCSI” devices). They can conform to either the SCSI-2 or SCSI-3 protocols. They have a 50-pin connection to the SCSI bus.

• Wide SCSI devices can transfer two bytes of data simultaneously (“16-bit SCSI”).

They usually have a single, 68-pin connection to the SCSI bus. (This physical arrangement is part of the SCSI-3 specification.) They may support either SCSI-2 or SCSI-3 protocols. Wide and narrow devices can simultaneously be connected to the same bus without problem, provided certain rules are followed.

• Fast SCSI can transfer data at up to 10 MB/sec, using a cable of up to 6 meters

total length.

• Ultra SCSI can transfer data at up to 20 MB/sec, but the cable length cannot

exceed 3 meters (it is also known as “Fast20”).

• Ultra2 SCSI can transfer data at up to 80 MB/sec, using a cable of up to 12

meters.

• Ultra160 SCSI can transfer data at up to 160 MB/sec, using a cable of up to 12

meters.

• Ultra320 SCSI can transfer data at up to 320 MB/sec, using a cable of up to 12

meters.

Ultra SCSI supports both SE and LVD interfaces. Although Ultra2 SCSI and above can support SE devices, this is not recommended as the whole bus is slowed to Ultra speeds; instead, use LVD devices only.

HP’s Ultrium drives are Ultra-320 compatible devices. They should be used only on LVD host bus adapters for maximum performance.

sequential access Sequential access devices store data sequentially in the order in which it is received.

Tape devices are the most common sequential access devices. Devices such as disk drives are direct access devices, where data is stored in blocks, not necessarily sequentially. Direct access allows speedy retrieval, but is significantly more costly.

HP Ultrium drives technical reference manual, volume 5: UNIX configuration guide 31

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Index

A

AIX 17 ANSI 5 asynchronous data transfer 29 AT&T mode 29

B

Berkeley mode 29 BOT 29 buffered mode 29

C

compression 29 confirming installation 27

D

data transfer 29 device files

AIX 18 IBM (AIX) 17

Sun workstations 23 direct access 31 documents, related 5

F

fast SCSI 31 fibre channel 30 filemarks 30 filenames under AIX 18

H

HP Alpha 15 HP-UX systems 11

determining attached devices 11

I

IBM (AIX) 17

determining SCSI ID 17

device files 17 immediate mode 30

infinite flush 30 installation, verifying 27

L

Linux 19

determining SCSI ID 19 LUN 30 LVD SCSI 31

M

mode

AT&T 29

Berkeley 29

immediate 30

N

narrow SCSI 31

P

PC-based UNIX - Linux 19

S

SAN 30 SCSI 5, 30 SCSI ID, determining

IBM (AIX) 17

Linux 19

Sun workstations 23 sequential access 31 single-ended SCSI 31 storage area network 30 Sun workstations

data values 25

determining SCSI ID 23

device files 23 synchronous data transfer 29 systems

HP-UX 11

Linux 19

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U

ultra SCSI 31

V

verifying installation 27

W

wide data transfer 29 wide SCSI 31

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HP Q1538-90925 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents

Related documents

Documents specific to HP Ultrium drives

Documentation map

General documents and standardization

Purpose of this manual

Ultrium drives in a library

Backup applications

Introduction

Determining attached devices

Adding stape and schgr (autoloader driver) to the kernel using sam

Add device files using sam

What next?

3 HP alpha UNIX

HP alpha UNIX 5.x

What next?

Determining the SCSI ID

Configuring the device files

Device filenames under AIX

Determining the SCSI ID (Linux)

Configuring on Linux systems

Using the seek and tell features of mt

What next?

6 Sun Systems, Solaris 8, 9, 10

Determining the SCSI ID

Configuring the Device Files

HP-Data Values

7 Verifying the Installation

Verifying the Installation of the Drive (UNIX)

To verify the installation:

Example

Glossary

Index