HP Archive Backup System for OpenVMS Guide to Operations

Troubleshooting
12.6 RDF (Remote Device Facility)
The value of the block length is specified to the underlying gtar backup engine as a blocking factor.
The blocking factor is defined as a multiple of 512 bytes. The default block length passed to
gtar is “-b20”. To determine an appropriate blocking factor or block length for a specific situation,
follow these steps:
Step 1. Divide the size of the disk (in bytes) by 99999
Step 2. Divide the resulting number by 512
Step 3.
Round up to the next whole number
For example, if the disk size is approximately 30,000,000,000 bytes (30 GB), use the following
formula:
30,000,000,000 / 999999 / 512 = 58.59 or 59
This results in a blocking factor of “-b59”.
You can modify the default block length from the GUI for Windows or UNIX save or restore
request on the Agent Qualifiers window. Specify this value in the Agent Qualifiers window.
Restriction:
ABS will not produce the correct results if the value exceeds “-b127”. If the disk is large enough
to exceed this amount, create more than one save request for that particular disk.
To modify the blocking factor, use the procedure described in Table 12–2.
Table 12–2 Modifying the Blocking Factor using MDMSview GUI
Step
Action
1. Invoke MDMSview GUI
2. Click Objects tab
12.5.6 Files Larger than 2gb
3. Select Selection Object either from the Tree or the Right panel.
4. Click on the appropriate Selection Name.
5. The attributes screen of the selected Selection Object is displayed on the right panel.
6. Enter the required Blocking Factor value in the Agent Qualifiers option's Text box.
7. Click Set Button, to update the changes made to the selected Selection Object.
Restore requirement:
When restoring data from a save request where the blocking factor has been modified, you must
specify the same blocking factor that was specified on the save request. Otherwise, the restore
request will fail due to an invalid block size on the tape. As a default, ABS uses 10240.
If you are attempting to backup files larger than 2gb on a Windows or Unix system, you may
received errors indicating that the file was not saved. The Windows gtar image we provide is not
able to backup these files.
12.6RDF (Remote Device Facility)
When errors occur with RDF (RDEV) devices, you should check your RDF setup and log files in
the directories pointed to by the logical names TTI_RDEV and TTI_RDF. There are log files
called RDCLIENT_.LOG and RDSERVER_.LOG. Also see the RDF documen-
12-10 Troubleshooting