Virtual Storage Console(VSC): Scaling for larger environments
Applies to
- Unified Appliance 9.x
- ONTAP Tools for VMware vSphere (OTV) 9.x
- Virtual Storage Console (VSC) 9.x
- VASA Provider (VP) 9.x
- Storage Replication Adapter (SRA) 9.x
Issue
By default, deploying the NetApp Unified Appliance (rebranded as OTV in 9.8 and later) which includes VSC, VP, and SRA "out of box" is sufficient for most small to medium size environments. However, it may be necessary to scale the appliance if the following signs of resource contention are seen:
- There is evidence of high CPU and / or memory utilization. For example, the following screenshot shows the output of 'top' which was run from the appliance's diagnostic shell. This shows very high CPU utilization for the vpserver daemon (i.e. the service for VASA Provider and SRA):
- A review of the appliance's vvolvp.log or netapp.log shows evidence of numerous long running ZAPI calls. For example, the following "slow-zapi" calls take anywhere from 10 to 25 seconds to complete:
11/06/17 EST 11:47:09 [periodic-rediscover-flexvol] slow-zapi-653741 192.168.0.33: 25629 ms
11/06/17 EST 11:47:47 [periodic-rediscover-flexvol] slow-zapi-653755 192.168.0.33: 10469 ms
11/06/17 EST 11:48:02 [periodic-rediscover-flexvol] slow-zapi-653756 192.168.0.33: 14898 ms
11/06/17 EST 11:48:22 [periodic-rediscover-flexvol] slow-zapi-653762 192.168.0.33: 10011 ms
Note: To view the vvolvp.log, you can download an appliance log bundle. For instructions on collecting a SRA Appliance log bundle, see KB: Storage Replication Adapter: How to collect logs from a SRA appliance
- There is evidence that discovery operations take a significant amount of time to complete. This can be established by reviewing the "periodicslow" files located in /logs/rightnows directory of an appliance log bundle. Seeing a value of 30 minutes or more consistently in the "In Flight Duration" column for discovery tasks may indicate that discovery is impacting performance on the appliance: