The log storage capacity for the Collector Group might display as 0MB if the disk pairs are not enabled for logging in the Log Collectors. To enable the disk pairs:
Resolve Zero Log Storage for a Collector Group
Select Panorama > Managed Collectors and edit each Log Collector in the Collector Group as follows.
Select Disks and Add each RAID disk pair.
Click OK and Commit, set the Commit Type to Panorama, and click Commit again.
Click OK and Commit, set the Commit Type to Collector Group, select the Collector Group, and click Commit again.
Select Panorama > Managed Collectors and verify that the configuration of each Log Collector is synchronized with Panorama. The Configuration Status column should display In Sync and the Run Time Status column should display connected.
Click Statistics in the last column for each Log Collector and verify that the disk pairs are Enabled and Available.

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