SUMMARY
This articles provides instruction on how to verify whether a system is using dedupNT or dedupDB
ISSUE
This articles provides instruction on how to verify whether a system is using dedupNT or dedupDB.
DedupNT and dedupDB are technologies used in Unitrends deduplication technology. As backup is deduplicated, the duplicate blocks are tracking using hashes. DedupNT and dedupDB provide two unique methods for maintaining the hash references. DedupNT and dedupDB cannot be used simultaneously and the technology must be chosen at the time of implementation. Once a backup is performed, the technology cannot be changes without data loss.
DedupNT maintains a flat file database for tracking hashes which reference the blocks required to unhash a backup.
DedupDB tracks hashes with the Unitrends postgres database.
RESOLUTION
Example shows hashes stored in the Unitrends postgres database:
[root@unitrends ~# psql -c "select * from bp.hash_values limit 1" hash_id | hash_type | hashed_length | hash_value | sis_offset | compressed_length ---------+-----------+---------------+------------------------------------------------------------------------------------------------------------------------------------+- -------------+------------------- 477339 | sha512 | 1048576 | \x8eba449c1278c912d6f9eef12a36f497127d679ba28de5c54a8be0146df61b6b4b18d70dfa4b2fef06258c003d1bf2893d20ad672425e809c46a8c0898fe8805 | 340093353984 | 155728 (1 row)
The example shows the flat file metadata database does not exist on this system. This indicates that dedupNT is NOT being used.
[root@unitrends ~]# ls -ralsth /usr/bp/data/hashMetadata ls: cannot access /usr/bp/data/hashmetadata: No such file or directory
All systems running Unitrends software 9.2 or higher will list the "MetadataGeneration" in the master.ini.
[root@VMware_UEB ~]# grep MetadataGeneration /usr/bp/bpinit/master.ini MetadataGeneration=0
MetadataGeneration=0 indicates dedupDB is being used.
MetadataGeneration=1 indicates dedupNT is being used.
Note: If you see MetadataGeneration=1 AND there are hashes listed in database from the PSQL query from above, that this will indicate a failed NT to DB migration, you will need to contact support for the NT to DB migration process to be run manually.
TASKS
The platform_capabilities file will indicate if a system is eligible to use dedupNT. If dedupNT is listed in /var/opt/unitrends/platform_capabilities, the system can be configured to use dedupNT however this must be done on the initial implementation to avoid data lost. Once a backup is performed, the technology cannot be changes without data loss.
The example below does not show dedupNT is available.
[root@unitrends ~]# cat /var/opt/unitrends/platform_capabilities Recovery-823 open_license ui:rrc rebuild_disk_mode:Recovery-730 legacy_archiving_mode:Rec823 max_backup:13000 deduplication replication vmware_ir hyperv_ir failover_virtualization:Unitrends.appliance_VMware.host_Hyper-V.host archive_reject_usb database_separate_filesystem:/var/opt/unitrends/database/UnitrendsDataBase inlineDedup
NOTES
Deduplication, dedup generation