About Disk Archiving

Archiving is the process of copying a file from online disk to archive media. With disk archiving, the archive medium is online disks in a file system.

Disk archiving can be implemented so that the files from one file system are archived to another file system on the same host or to another file system on a different host. When disk archiving is configured for two host systems, the systems act as a client and a server. The host system where the source files reside is the client and the host system where the archive copies are written is the server.

The file system to which the archive files are written can be any UNIX file system. However, if disk archive copies are written to a different host, that host must have at least one QFS or SAM-QFS file system installed on it.

The archiver treats files archived to disk volumes in the same way as files archived to volumes in a library. You can make one, two, three, or four archive copies. If you are making multiple archive copies, you can write one of the archive copies to disk volumes and write the other archive copies to removable media volumes. In addition, if you archive to disk volumes that are in an archived file system, the archive copies are also archived according to the archiver.cmd file rules for that file system.

When you plan disk archiving for your site, consider the following guidelines:

• Create disk volumes on a different disk from the one on which the original files reside.

• Make more than one archive copy and write to more than one type of archive media. For example, create archive copy 1 to disk volumes, copy 2 to tape, and copy 3 to magneto-optical disc.

• If you are archiving files to a file system on a server system, the archive copies can also be written to removable media cartridges in a library attached to that server system.

The following list summarizes some of the similarities and differences between archiving to disk volumes and archiving to removable media:

• Archive copies in disk volumes are not recorded in a catalog.

• Archive copies in disk volumes do not appear in the historian.

• Archiving to disk volumes does not rely on entries in the mcf file. Instead, you specify disk archive sets in the archiver.cmd file and you define disk volumes in /etc/opt/SUNWsamfs/diskvols.conf.

• To archive to disk volumes, you must define disk archive sets in the archiver.cmd file before mounting the file system. When you archive to removable media volumes, you can begin archiving after the file system is mounted without changing any of the default values in the archiver.cmd file.

About the diskvols.conf File

Disk archiving does not rely on entries in the mcf file. You specify disk archive sets in the archiver.cmd file and you define disk volumes in /etc/opt/SUNWsamfs/diskvols.conf.

Create the diskvols.conf file on the system where the source files reside. Depending on where the archive copies are written, the diskvols.conf file contains the following information:

• If the archive copies are written to a file system on the same host system, the diskvols.conf file defines the VSNs and the paths to each VSN.

• If the archive copies are written to a different host system, the diskvols.conf file contains the host name of that server system. In this case, create another diskvols.conf file on the server system that specifies the host names of the client systems.

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Caution - Be very careful when configuring the recycler if you are using disk archiving in an environment with multiple SAM-QFS servers. The diskvols.conf file for each SAM-QFS server must point to a unique set of disk volume resource specifications (disk archiving target directories). If any of the target directories are shared by the SAM-QFS servers, running the recycler from one SAM-QFS server destroys the disk archive data that is managed by the other SAM-QFS server.

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The diskvols.conf file must contain the following information:

VSN-name [host-name:] path

The following additional rules apply to the diskvols.conf file:

• Start each comment line with a hash character (#). All text to the right of the # is ignored.

• To continue a line, put an apostrophe character (') at the end.

For more information, see diskvols.conf(4) in Sun QFS and Sun Storage Archive Manager Reference Manual.

Disk Archiving Directives

When archiving to disk volumes, the archiver recognizes the directives that define archive sets and recycling and ignores directives that pertain to removable media cartridges. The archiver recognizes the directives described in the following sections:

• Archive Set Copy Parameters Exceptions

• Archive Directives Exceptions

• Recycling Directives Exceptions

• vsn Directives

• clients and endclients Directives

• -recycle minobs Recycler Directive

Archive Set Copy Parameters Exceptions

All the parameters described in Archive Set Copy Parameters are valid except for the following:

• -reserve method

• -tapenonstop

To configure an archive set to write multiple, simultaneous disk archive streams, use the -drives parameter. In this configuration, volumes are selected in a round-robin manner starting with the volume that has the highest percentage of available space. However, if the parameter -fillvsns is specified, the volume with the least percentage of remaining space is selected first.

Archive Directives Exceptions

All the directives described in Chapter 11, Archive Directives (archiver.cmd) are valid except for the following:

• ovflmin min-size

Recycling Directives Exceptions

All of the directives described in Table 16-3 are valid except for the following:

• -recycle_dataquantity size

• -recycle_vsncount count

• recycle_hwm

vsn Directives

The following directives are valid:

• vsns and endvsns

• vsnpools and endvsnpools

Disk volumes are supported in the VSN associations section and are defined with a dk media type. The volumes are identified by one or more VSN expression keywords. You can also specify VSN pools from which disk volumes are to be selected, as shown in the following example.

vsnpools
data_pool dk disk0[0-5]
endvsnpools

vsns
arset0.1 dk disk10 disk1[2-5]
arset1.1 dk -pool data_pool
endvsns

Disk archiving can be carried out on the StorageTek 5800 system. The StorageTek 5800 is an online storage appliance with an integrated hardware and software architecture in which the disk-based storage nodes are arranged in a symmetric cluster. The media abbreviation for StorageTek 5800 disk archives in the vsns directives is cb.

clients and endclients Directives

The clients and endclients directives are valid. If you archive files from a client host to a server host, the server system must have a diskvols.conf file that contains the name of the client system. The format for these directives is shown in following example. For client-system, specify the host name of the client system that contains the source files.

clients
client-system1
client-system2
...
endclients

-recycle minobs Recycler Directive

The -recycle_minobs _percent_ recycler directive is valid. This option is used to set a threshold for the recycler's rearchiving process for disk archives. The default threshold is 50 percent. When the percentage of obsolete files within an archived tar file on the disk reaches this threshold, the recycler moves the valid files from the archive into a new tar file. When all of the valid files have been moved, the original tar file is marked as a candidate for removal from the disk archive. This option is ignored for removable media recycling.

How to Enable Disk Archiving on the Client Host

Perform this procedure on the client host system that contains the files to be archived. As an alternative, you can use the SAM-QFS Manager interface to specify an archive policy that archives to disk volumes. This action updates both the archiver.cmd file and the diskvols.conf file.

1. Become superuser on the client host system.
2. Create or open the file /etc/opt/SUNWsamfs/archiver.cmd.
3. Add disk archive set directives as in the following example:

   #
   vsns
   archset1.1 dk disk01
   archset2.1 dk disk02
   archset3.1 dk disk03
   endvsns

   Disk archiving can also be carried out on the StorageTek 5800 system. The StorageTek 5800 is an online storage appliance with an integrated hardware and software architecture in which the disk-based storage nodes are arranged in a symmetric cluster. The media abbreviation for StorageTek 5800 disk archives in the vsns directives is cb.

   For more information about specifying archive sets, see archiver.cmd(4) in Sun QFS and Sun Storage Archive Manager Reference Manual or see Chapter 12, Archive Set Directives (archiver.cmd).

4. Save and close the archiver.cmd file.
5. Create a file named diskvols.conf.
6. Specify the directories to which the archive copies will be written.

   The following example shows a diskvols.conf file that archives files from three archive sets. The disk volumes named disk01 and disk02 reside in a file system on the server system named otherserver. Disk volume disk03 resides on the same host as the files to be archived.

   # This is file sourceserver:/etc/opt/SUNWsamfs/diskvols.conf
   # on the client
   #
   # VSN_name [host_name:] path
   #
   disk01 otherserver:/sam/archset1
   disk02 otherserver:/sam/archset2
   disk03 /sam/archset3 

7. Save and close the diskvols.conf file.
8. Create directories in the file system to which the archive copies will be written.

   For example:

   # mkdir sam
   # cd sam
   # mkdir archset1
   # mkdir archset2

9. Verify the syntax in the archiver.cmd file:

   # archiver -lv

10. If any errors are found, correct them before proceeding.

How to Configure Disk Archiving on the Server Host

Perform this procedure only if you are writing your archive copies to a host system that is different from the host system upon which the source files reside. At least one QFS or SAM-QFS file system must be created on this host. If you create source files and write archive copies to the same host system, you do not need to perform this procedure.

In this situation, you are creating a client/server environment:

• The client is the host that contains the source files.

• The server is the host to which the archive copies are written.

1. Become superuser on the server.
2. Create or open the file /etc/opt/SUNWsamfs/archiver.cmd.
3. Edit the archiver.cmd file to add disk archive set directives as in the following example:

   #
   vsns
   archset1.1 dk disk01
   archset2.1 dk disk02
   archset3.1 dk disk03
   endvsns

   For more information about specifying archive sets, see archiver.cmd(4) in Sun QFS and Sun Storage Archive Manager Reference Manual or see Chapter 12, Archive Set Directives (archiver.cmd).

4. Save and close the file.
5. Change to the file system to which you want to write the archive copies.

   For example:

   # cd /ufs1

6. Create directories in the file system.

   For example:

   # mkdir sam
   # cd sam
   # mkdir archset1
   # mkdir archset2

7. Create the file /etc/opt/SUNWsamfs/diskvols.conf.
8. Specfiy the clients and endclients directives and the name of the client.

   The name of the client in the following example is sourceserver.

   # This is
   # file destination_server:/etc/opt/SUNWsamfs/diskvols.conf
   # on the server
   #
   clients
   sourceserver
   endclients

9. Save and close the diskvols.conf file.

How to Enable Disk Archiving

You can enable disk archiving at any time. The procedure assumes that you are adding disk archiving to an existing archiving configuration.

Before You Begin

Make certain that the server host to which you want to write your disk archive copies has at least one QFS or SAM-QFS file system installed on it.

1. Become superuser on the host system that contains the files to be archived.
2. Enable or configure disk archiving on the client and server hosts.

   Follow the How to Enable Disk Archiving on the Client Host procedure or How to Configure Disk Archiving on the Server Host procedure.

3. On the client host, propagate the configuration file changes and restart the system.

   # samd config

4. If you are archiving to disk on a different host, follow these steps:
   1. Become superuser on the server host.
   2. Use the samd config command to propagate the configuration file changes and restart the destination system.
5. If you are archiving to a StorageTek 5800 system, upgrade the StorageTek 5800 metadata schema configuration.

   Follow the procedures documented in the StorageTek 5800 System Administration Guide and use the XML overlay in the following example to define the metadata that is used by SAM-QFS.

   <<?xml version="1.0" encoding="UTF-8"?>
   
   <metadataConfig>
   <schema>
   <namespace name="com">
   <namespace name="sun">
   <namespace name="samfs">
   <field name="archiveId" type="string" indexable="true"/>
   <field name="fileName" type="string" indexable="true"/>
   <field name="modTime" type="time" indexable="true"/>
   </namespace>
   </namespace>
   </namespace>
   </schema>
   
   <fsViews>
   </fsViews>
   
   </metadataConfig>

Disk Archiving Examples

The following examples show disk archiving configurations.

Example 1

In this example, VSNs identified as disk01, disk02, and disk04 are written to pluto, the host system where the original source files reside. VSN disk03 is written to a VSN on server system mars.

The following example shows the diskvols.conf file that resides on client system pluto.

# This is file /etc/opt/SUNWsamfs/diskvols.conf on pluto
# VSN Name [Host Name:]Path
#
disk01 /sam_arch1
disk02 /sam_arch2/proj_1
disk03 mars:/sam_arch3/proj_3
disk04 /sam_arch4/proj_4

The following example shows the diskvols.conf file on server system mars.

# This is file /etc/opt/SUNWsamfs/diskvols.conf on mars
#
clients
pluto
endclients

The following example shows a fragment of the archiver.cmd file on pluto.

vsns
arset1.2 dk disk01
arset2.2 dk disk02 disk04
arset3.2 dk disk03
endvsns

Example 2

In this example, file /sam1/testdir0/filea is in the archive set for arset0.1, and the archiver copies the content of this file to the destination path /sam_arch1.

The following example shows the diskvols.conf file.

# This is file /etc/opt/SUNWsamfs/diskvols.conf
#
# VSN Name [Host Name:]Path
#
disk01 /sam_arch1
disk02 /sam_arch12/proj_1

The following example shows the archiver.cmd file lines that pertain to disk archiving:

.
vsns
arset0.1 dk disk01
endvsns .

The following example shows output from the sls(1) command for file filea, which was archived to disk. Note the following information about copy 1:

• dk is the media type for disk archive media

• disk01 is the VSN

• f192 is the path to the disk archive tar file

# sls -D /sam1/testdir0/filea
/sam1/testdir0/filea:
mode: -rw-r----- links: 1 owner: root group: other
length: 797904 admin id: 0 inode: 3134.49
archdone;
copy 1: ---- Dec 16 14:03 c0.1354 dk disk01 f192
access: Dec 19 10:29 modification: Dec 16 13:56
changed: Dec 16 13:56 attributes: Dec 19 10:29
creation: Dec 16 13:56 residence: Dec 19 10:32

Example 3

In this example, file /sam2/my_proj/fileb is on client host snickers in archive set arset0.1, and the archiver copies the content of this file to the destination path /sam_arch1 on server host mars.

The following example shows the diskvols.conf file on snickers.

# This is file /etc/opt/SUNWsamfs/diskvols.conf on snickers
#
# VSN Name [Host Name:]Path
#
disk01 mars:/sam_arch1

The following example shows the diskvols.conf file on mars.

# This is file /etc/opt/SUNWsamfs/diskvols.conf on mars
#
clients
snickers
endclients

The following example shows the directives in the archiver.cmd file that relate to this example.

.
vsns
arset0.1 dk disk01
endvsns .