Post-deduplication Replication Fails Due to SIR Swap Space Exhaustion

Publication Date:  2013-05-28 Views:  597 Downloads:  0
Issue Description
Product and version: VTL6000 V100R003C01
The symptom is:
 Deduplicated data is replicated from the production end to the disaster recovery end. If the amount of data replication is small, the replication succeeds. If the amount is large, the SIR server on the disaster recovery end reports error. Go to SIR Console, export X ray information, as the following.
Neotelvtl6000sir rde: IPSTOR||1315615484||E||50906||Store data block requested for folder %1 failed. Reason is %2.||5CB74036-CE90-AD9F-8920-D05183AC39B6||Folder has failed (RDE_ERROR_GENERAL_CLIENT_ERROR)
 Go to VTL Console, export X ray information which shows that VTL server on the production end generates a log indicating that the connection to the SIR server breaks down and that deduplicated data fails to be replicated.
Teraco-HAvtl-B ipstorcomm: IPSTOR||1315610499||E||0x0000c566||Policy %1, Tape [%2] unique data replication terminated with error: %3.||Deduplication Policy OSMS DATA||273A0002||SIR server not accessible
Alarm Information
None.
Handling Process
Step 1 Log in to the SIR server on the disaster recovery end using PuTTY or a Secure Shell (SSH) tool (the default user name is root and the password Admin@storage).
Step 2 Run the sir stop all command to stop the SIR server service on the disaster recovery end.
Step 3 Run the cd /usr/local/sir/bin command to access the bin folder.
Step 4 Run the vi rdereposit.sh command to modify parameters of the rdereposit.sh file.

if [ "$MB_MEMORY" -ge 2048 ]
then
         if [ "`xmlstat $ISCONF isnasenabled`" = "1" ]
          then
               MB_TO_USE=$((MB_MEMORY/2))
          else
               MB_TO_USE=$((MB_MEMORY-8192))
          fi

Step 5 Save the file and exit. Then run the sir start all command to start all services on the SIR server.
Step 6 Go to VTL Console, execute the replication policy.
For details, see Configuring Remote Replication in OceanStor VTL6000 Virtual Tape Library Initial Configuration Guide.
Step 7 Run the top command on the SIR server of the disaster recovery end to view the usage of swap space.

The remaining swap space is equal to the total space.
Step 8 The replication task succeeds. If fails, contact R&D engineers.
----End
Root Cause
Run the top command on the SIR server of the disaster recovery end to view the usage of memory, CPU, and swap space. The remaining swap space is found to have decreased to 0 KB. However, in normal circumstances, the remaining swap space is close to the total space. Therefore, the cause of the post-deduplication replication is swap space exhaustion.
Suggestions
None.

END