Cause: On AIX MediaAgents, the presence of a number of SCSI adaptors
may result in slowing down the detection process. If you know that some of these
adaptors are not required by the MediaAgent, you can skip them during the detection process as described in below.
Use the following format to add the list of adapters that must be skipped
during device detection.
adapter <adapter name>
For example:
adapter scsi2
adapter fscsi1
Note the following:
Entries are case-sensitive
Adapters to be skipped can be specified in any order
Each entry must identify a single adapter to be skipped
Tape Spanning failure on AIX MediaAgents with Native Drivers
This might occur for the following reason:
Cause: On AIX MediaAgents with IBM library and ATAPE drivers and if Use Native device driver for data transfer for tape media
option in the MediaAgent Properties is enabled, the
MediaAgent software sets the drive attribute for
trailer_labels to yes when a data
protection operation is initiated. If this
attribute is set to no, (For example, by other applications
sharing the library) data protections operations may fail when the operation spans
to another tape.
Use the following command to see the drive attribute for
trailer_labels.
lsattr –El rmtX
Job Failures in Solaris MediaAgents
Using Native Drivers
Use the following steps if you find Data Protection Operation failing on
Solaris MediaAgents when Native Drivers are enabled.
To configure native tape drive support on Solaris the native ST device nodes
should be added to /kernel/drv/st.conf and bound
to all the tape drive LUNs which are to be used.
For example:
Add the following lines in /kernel/drv/st.conf
to bind tape drives having Target 0 and Lun 1, and Target
0 and Lun 2 with native driver:
name="st" class="scsi" target=0 lun=1;
name="st" class="scsi" target=0 lun=2;
Also make sure to reload the ST drivers using the following commands:
rem_drv st
add_drv st
Adjust Timeout Value for SCSI Commands on MediaAgents
If you see devices timing out (in MediaManager.log file) and jobs failing as
a result, you may want to adjust the timeout value for SCSI commands to these
devices.
On Windows, the system uses native drivers and the timeout values are
determined by the drivers.
The SCSI timeout values may only apply to the SCSI
commands associated to the library. The following are the SCSI timeout registry values
that are available on Windows:
On UNIX it's possible to specify timeout values for any SCSI command as long
as the command is delivered using the pass-through driver as arm changers are
always accessed using pass-through nodes on all UNIX platforms.
Tape drives by default are accessed using native drivers on AIX, Solaris,
HP-UX, Linux and Tru64. Native drivers do not offer a way to customize SCSI
timeouts. However, it is possible to enable pass-through mechanism from the
CommCell Console by disabling the Use Native device driver for data transfer for tape media
option in the MediaAgent Properties.
Once this is done pass through SCSI timeouts can be customized by modifying
the following registry values:
These are the rules that should be observed while making the changes:
All timeouts are in seconds.
If a timeout is inside asterisks (e.g. *600*), it means that this is a
default timeout. If you want to change the default value, you must remove
the asterisks, or else the system will revert the timeout back to the
default. This is done to simplify upgrades.
If you want to change timeout for a command, which is explicitly listed
in registry, you must put the new value on that respective line.
If you want to change timeout for an unlisted command, you have two
ways:
You can change the value for the DEFAULT timeout,
You can add the unlisted command by inserting a line like "CDB_XX
<timeout>" where XX is the command's cdb[0] in hex.
Work-Around for a Failed MediaAgent
If a MediaAgent has failed and there are other MediaAgents in the CommCell,
you can re-establish backup/restore operations for the affected client
computers. Use any one of the following solutions.
To reestablish client operations when a MediaAgent has failed:
Create new storage policies where the primary copy transfers its backup
data through a working MediaAgent and to a working library.
For tape libraries, ensure that the MediaAgent(s) that control both the
library and target drive pool are in working order. (For shared libraries,
different MediaAgents can control the library and a given drive pool. To
identify these MediaAgents, check both the Library Properties and Drive
Pool Properties dialog boxes.)
For disk libraries, ensure the MediaAgent that controls the
disk library is in working order. (To identify the MediaAgent,
check the related Library Properties dialog box.)
For each of the subclients of the affected client computers, perform the
following:
From the CommCell Browser, open the Subclient Properties dialog box.
Click the Storage Devices tab and select one of the newly created
storage policies.
Once the subclients of the affected client computers are
associated to working libraries, you can resume backup operations.
Use existing storage policies to back up the client computers that
are affected by the failed MediaAgent. To do this, identify those storage
policies where the primary copy transfers its backup data through a working
MediaAgent and to a working library.
For tape libraries, ensure that the MediaAgent(s) that control both the
library and target drive pool are in working order. (For shared libraries,
different MediaAgents can control the library and a given drive pool. To
identify these MediaAgents, check both the Library Properties and Drive
Pool Properties dialog boxes.)
For disk libraries, ensure the MediaAgent that controls the
disk library is in working order. (To identify the MediaAgent,
check the related Library Properties dialog box.)
For each of the subclients of the affected client computers, perform the
following:
From the CommCell Browser, open the Subclient Properties dialog box.
Click the Storage Devices tab and select one of the newly created
storage policies.
Once the subclients of the affected client computers are associated to
working libraries, you can resume backup operations.
If a storage policy has a secondary copy and this copy points to another
MediaAgent, and if Auxiliary Copies are performed regularly (therefore making
available backed up data in an additional manner), promote the secondary copy to
a primary copy.
Move a Library to Another MediaAgent Without Data Loss
In some situations you may have the need to move a library from one
MediaAgent to another due to re-configuration or other requirements.
The following procedure provides step-by-step instructions on how to perform
this operation.
Detach the library and attach it to the new MediaAgent and make sure
that the hardware is visible to the operating system. See
Driver Configurations
for more information.
If necessary run a quick backup to verify that the devices are
functioning correctly.
Move a MediaAgent Without Data Loss
In some situations you may have the need to move a MediaAgent from one computer
to another. For example:
You may want to move the MediaAgent to another computer when you move the
pilot version of the software to the production environment.
You may want to separate the MediaAgent from a CommServe, if they were installed
together.
You may want to move a MediaAgent to a more powerful computer or such
similar re-configuration needs.
You will require an additional MediaAgent license to perform this
operation.
The following procedure provides step-by-step instructions on how to perform
this operation.
Detach the library and attach it to the new computer and make sure that
the hardware is visible to the operating system. See
Driver Configurations for
more information.
Install the MediaAgent software in the new computer. See
MediaAgent Deployment for more
information.
If the index cache is configured in the old MediaAgent, move the index
cache to the new MediaAgent. (See
Move an Index Cache
for step-by-step instructions.)
If necessary run a quick backup to verify that the devices are functioning
correctly.
Uninstall the MediaAgent software from the original computer. See
Uninstall Components
for more information.
WARNING
Do not deconfigure the library at any point.
Also do not uninstall the old MediaAgent until the devices start functioning
in the new MediaAgent.
Separate the CommServe from a CommServe-MediaAgent Computer
In some situations you may want to separate the CommServe from a MediaAgent
computer, (with or without a File system iDataAgent) if they were installed
together. For example, you may want to move the CommServe to a more powerful computer or such
similar re-configuration needs.
The following procedure provides step-by-step instructions on how to perform
this operation.
You can also use this procedure to relocate a CommServe and MediaAgent which
are installed together, to two separate computers.
You will require an additional MediaAgent license to perform this
operation.
Source Computer
1.
Copy the index cache folder (and the job results folder if the (File
system iDataAgent is
installed) to another location.
2.
Perform a Disaster Recover Backup.
Verify and ensure that the Disaster Recovery Backup completes
successfully. Also note down the location of the disaster recovery backup
file. (For a more detailed discussion, see
Phases of Disaster Recovery Backups.)
During MediaAgent installation make sure to specify the index cache
to the location in which it was copied in step 1. If you are unable to do
so, perform the steps described in
Manually Relocate
the Index Cache.
10.
Open the CommCell Console and change the MediaAgent name associated with
the library.
If you have a disk library, make sure that the mount path is
pointing to the appropriate location. If necessary move the mount path
to the appropriate location and then change the location of the mount
path.
