Environment
Novell Open Enterprise Server 11 (OES 11) Linux Support Pack 1
Novell Open Enterprise Server 11 (OES 11) Linux Support Pack 2
Novell Open Enterprise Server 11 (OES 11) Linux Support Pack 2
Situation
Following a OES11 SP1 to OES11 SP2 system upgrade, any xattr based backup application will perform a full backup of the updated OES11 SP2 server.
Resolution
The
problem has been fixed, and a solution has been published with the
release of the January 2015 OES Scheduled Maintenance patches.
Cause
The root cause for this problem was two-folded :
OES 11 SP1 has zMOD_DIR_QUOTA (0x02000000) set, while SP2 has it cleared. Both OES11 SP1 and OES11 SP2 use 0x7fffffffffffffff to represent no quota limit. Objects with specific quotas are reported the same under SP1 and SP2. The nvm_quota_limit has the specific quota, and nvm_modify_mask has zMOD_DIR_QUOTA set.
Therefor, regardless of volume DIR QUOTA setting, upgrading from OES11 SP1 to OES11 SP2 will causes NSS to return different netware.metadata xattr's when an object has no quota, even when no change to the object has occurred.
- Upgrading from OES11 SP1 to OES11 SP2 on a volume with DIR QUOTAS _disabled_ causes the nvm_quota_limit to change.
- Upgrading from OES11 SP1 to OES11 SP2 on a volume with DIR QUOTAS _enabled_ causes the nvm_modify_mask to change.
OES 11 SP1 has zMOD_DIR_QUOTA (0x02000000) set, while SP2 has it cleared. Both OES11 SP1 and OES11 SP2 use 0x7fffffffffffffff to represent no quota limit. Objects with specific quotas are reported the same under SP1 and SP2. The nvm_quota_limit has the specific quota, and nvm_modify_mask has zMOD_DIR_QUOTA set.
Therefor, regardless of volume DIR QUOTA setting, upgrading from OES11 SP1 to OES11 SP2 will causes NSS to return different netware.metadata xattr's when an object has no quota, even when no change to the object has occurred.
Additional Information
Note 1 :
When using any xattr based backup application to backup OES11, and migrating to OES11 SP2, it is important to not run into a problem where the backup application will perform a full data backup due to perceived NSS metadata changes following the migration to OES11 SP2.
This can be achieved by upgrading the OES11 SP2 server to the January 2015 OES Scheduled Maintenance patches first, prior to running any xattr based backup.
After applying the January 2015 OES Scheduled Maintenance patches, both OES11 SP1 and OES11 SP2 xattr metadata behavior is identical again.
Note 2:
When a OES11 SP1 server is upgraded to OES11 SP2 (pre OES11 SP2 January Scheduled Maintenance patch code base), the first time a xattr based backup will executed, this backup will always be a *full* backup since the xattr's are programmatically misinterpreted on OES11 SP2 versions (prior OES11 SP2 January Scheduled Maintenance patches).
It is important to understand that following the OES11 SP2 January Scheduled Maintenance patch installation the xattr misinterpretation is programmatically corrected to match the previous OES xattr behavior again, and so the first backup following the OES11 SP2 January Scheduled Maintenance patch installation will therefor automatically be a *full* backup again.
When using any xattr based backup application to backup OES11, and migrating to OES11 SP2, it is important to not run into a problem where the backup application will perform a full data backup due to perceived NSS metadata changes following the migration to OES11 SP2.
This can be achieved by upgrading the OES11 SP2 server to the January 2015 OES Scheduled Maintenance patches first, prior to running any xattr based backup.
After applying the January 2015 OES Scheduled Maintenance patches, both OES11 SP1 and OES11 SP2 xattr metadata behavior is identical again.
Note 2:
When a OES11 SP1 server is upgraded to OES11 SP2 (pre OES11 SP2 January Scheduled Maintenance patch code base), the first time a xattr based backup will executed, this backup will always be a *full* backup since the xattr's are programmatically misinterpreted on OES11 SP2 versions (prior OES11 SP2 January Scheduled Maintenance patches).
It is important to understand that following the OES11 SP2 January Scheduled Maintenance patch installation the xattr misinterpretation is programmatically corrected to match the previous OES xattr behavior again, and so the first backup following the OES11 SP2 January Scheduled Maintenance patch installation will therefor automatically be a *full* backup again.