The crawl status numbers on a replica all show zero
Summary: After configuring mirroring on the search appliance, the values listed on the replica's Google Seach Appliance > Content Sources > Diagnostics > Crawl Status (see 7.0 to 7.2 Admin Console mapping for prior page location) page in the Admin Console show zero for each value.
Cause: Replicas do not run a crawl service, so the information shown in Crawl Status is invalid.
Fix: Only use the master Admin Console when looking at the Crawl Status.
Additional Details: For more details about which tasks should be performed on replicas, please read Tasks Performed on Replica Search Appliances.