Restored online backup fails to start 4229 with 1124 in area 6

Restored online backup fails to start 4229 with 1124 in area 6
Subsequent online probkups also fail to start with error 1124 listing a different expected dbkey listed for the nul key in area 6
Key information is missing in the restored database that was present in the live database at the time the backup volume was created.
Not all restored online backups can be forced into.
PROBKUP online with the bibackup all switch still fails to start after PROREST
A restored offline PROBKUP starts without error and all data are available from the time of the live offline backup.
An online backup off the restored offline backup fails to start 1124
A PROCOPY of live can be accessed without error and all expected data are present
A restored online backup of the PROCOPY fails to start 1124

Full online probkups are not backing up the entire database
Comparing the HWM from prostrct statistics with the backup blocks written shows online volumes do not include all blocks to the HWM of each Area

Example, this database backup volume should be around 1.6 GB using 11955 backup blocks with a default -bf 34

PROBKUP online and PROREST complete without error.
Live db clean (DBTOOL,3 and IDXCHECK)
Online full probkup is run hourly without error
Restored online PROBKUPS were previously working for many years

The backup counter is working as designed.  There is a project to address this limitation in a future release.  The backup counter is 2 bytes so has a maximum value of 65535 . The backup counter is incremented in the Database Master Block every time a PROBKUP is run (online, offline; full, incremental).  For example, if one PROBKUP is taken every hour (online/offline/incremental), the counter will overflow in ~7 years. An enhancement has been requested but not been implemented in the product to date.

Once the backup counter overflows, the logic in online backup which determines if a block should be backed up, will then initially only backup 'new' database blocks that have never been backed up (ie empty blocks that have been formatted) and from that point on, these database blocks if they qualify and 'new' database blocks as the remaining blocks all have much higher backup counter values in them. 

The offline backup's logic is different and is not affected by the backup counter overflow. In otherwords, an offline probkup will be complete and a full restored database will result, but subsequent online probkups of this restore will suffer the same online backup counter overflow logic.

Upgrade to 11.7.5 (or later in 11.7.x group) or 12.0 (or later n 12.x group).

If upgrade is not possible use the workaround listed below.

Once the backup counter has overflowed,  the counters on all database blocks needs to be re-initialised. This can be achieved by:

1. A dump and load of the database
2. A tablemove/indexmove of all database objects to new Storage Areas, then remove the existing areas. This includes using 'PROUTIL -C mvsch' to re-initialise the current Schema Area blocks. Refer to Article Truncate the Schema Area with PROUTIL mvsch   

Each method has it's own pro's and con's which will need to be mooted per user case. Neither PROCOPY nor offline backup PROREST will reset block backup counters

For further information refer to Article  How many online probkups can be taken?