Troubleshooting
Problem
This technote identifies a defect where adding more groups to an IBM Rational ClearCase VOB using cleartool protectvob -add_group fails with "cleartool: Error: Problem starting vob_server for vob" and provides an altenative for removing groups from VOBs on UNIX and Linux.
Symptom
The cleartool protectvob -add_group fails with :
cleartool: Error: Problem starting vob_server for vob vobsmre:/asgard/project/bsc/vob-stg/ov.vbs
cleartool: Error: See albd_log or vob_log on host vobsmre
cleartool: Error: Operation "vobsvr_get_handle" failed: error detected by ClearCase subsystem.
The vob_log shows:
05/10/95 21:45:48 vob_server: Error: setgroups failed: Invalid argument
Cause
This is caused by the fact that the command is trying to add a group which would exceed the maximum number of groups allowed for the VOB's Additional Groups list.
The limitation on many UNIX and Linux operating systems is restricted to 16 groups.
ClearCase however allows up to 32 groups on the VOB's group list, and this feature tends to override the operating systems' threshold.
In many cases, the above error does not mean that the group did not get added to the Additional Groups list, but serves as an indicator of the problem with the VOB.
When the maximum groups for the operating system has been exceeded, the VOB is left in an unusable state.
Note: There are instances where no error occurs when adding too many groups to the VOB's group list, but the VOB still becomes corrupt (or in this same unusable state).
Resolving The Problem
This defect has been resolved in the following updates:
ClearCase 7.0 |
ClearCase - 7.0.0.0-RATL-RCC-IFIX02 CCLT - 7.0.0.0-RATL-RCCLT-IFIX02 |
Applying these updates will now allow ClearCase to perform a check against the number of groups added plus the number of groups already present to ensure the number is less than or equal to the allowed maximum.
After applying the patches, attempts to add more groups to a VOB than the OS supports (16 on UNIX and Linux) will result in the error:
VOB <name> already has <x> supplementary groups; only <n> more can be added.
WORKAROUND:
Check to see how many groups have been added to the VOB's group list using cleartool describe -long vob:\<VOB-tag>.
If an error similar to the above occurs, then you need to count the number of groups in the .identity directory under the VOB storage; look for the files in the form of, group.<groupID>.
Any groups over the count of sixteen must be removed from the VOB's group list.
Note: There can be up to 16 groups in the .identity directory, but 17 and greater cause the VOB to be inaccessible.
To make the VOB operational again remove groups > 16
You can try cleartool protectvob -delete_group, as detailed in technote 1147137. However, this has been known to fail in this situation.
The alternative is to delete the groups directly from the .identity directory:
- Unmount the VOB, cleartool umount \<vob-tag>, and kill the vob_server process
- Change directory to <vob-storage-dir>/.identity
- Run, rm group.<one-group-too-many>, to remove the files
- Mount the VOB, cleartool mount \<vob-tag>
- Confirm the error is resolved using, cleartool describe -long vob:\<vob-tag>
Note: All users that had this VOB mounted will need to umount, kill the process and mount the VOB as detailed in the above steps for the change to take affect.
Consult your system administrator or operating system manuals for assistance with any of the operating system commands.
Related Information
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Document Information
Modified date:
16 June 2018
UID
swg21126524