VM Image Selection

Depending on the deployment type, choose whether to use Single-disk or Four disks VM image for storing the Cisco Provider Connectivity Assurance Sensor Control data. Here are some key differences between these two approaches:

Single-disk

The total size allocation is 4 GB, with the storage disk set at 2 GB by default and configurable up to 4 GB.

Advantages:

• Recommended for smaller deployments
• Requires smaller disk space on the VM host
• Easier to deploy with NFVi management tools that support only one disk

Disadvantages:

• Shorter retention duration

Four disks

The total size allocation is 102 GB, with the storage disk set at 40 GB by default and configurable up to 100 GB.

Advantages:

• Recommended for larger deployments and for deployments that use flowbroker to store PCAP files
• Longer retention duration
• For example, 4000 sessions at 1-minute reporting period requires 40 GB
  

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  Note:

  The disk size calculation is based on the number of sessions, reporting interval, and retention time.

  Each session requires 500 bytes per result record (RR). A result record is produced at every reporting period.

  If we take the example of 4000 sessions, reporting at every 30 seconds with a retention time of 7 days:

  4000 sessions x 500 bytes (RR size) x 2 (number of record per minute) x 60 minutes x 24 hours x 7 days = 40.3 GB

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Disadvantages:

• Requires larger disk space on the VM host

Once you have selected which approach to use, see Managing Disk Storage for instructions on how to increase the disk storage up to the allowable limit for your VM image.