Portworx Enterprise - Scenarios Where the Replica Count Label and Actual Replica Count May Differ

When a volume is created, it is assigned a label named "repl" whose value indicates the replica count. This KB explains the different scenarios in which a mismatch between the configured replica count and the "repl" label value can occur.

Scenario 1: Manual Update of Volume Replica Count

• The volume replica count was manually modified using the pxctl volume ha-update command
• The corresponding repl label was not updated, resulting in a mismatch

Scenario 2: Manual Update of Volume Label

• The repl label was manually updated using the pxctl CLI
• The actual volume replica count was not modified to match the updated label

Scenario 3: License Expiry with Replica Node Decommissioned

• The Portworx license had expired, preventing any replica scale-up operations
• One of the replica nodes was decommissioned
• During decommissioning, replicas were reduced first
• Replica re-addition failed due to the expired license
• Volume is currently running with fewer replicas than originally configured

Scenario 4: When License is expired and one node in PX cluster was down for more than 24 hours

• Portworx license had expired, blocking any replica increase operations
• One replica node was in a down state for an extended period (>24 hours)
• Portworx removed replicas from the affected node after the replica move timeout was exceeded
• During the replica movement process, replicas were reduced first
• Replica re-addition failed due to the expired license
• The volume is currently running with fewer replicas than originally configured

Scenario 5: When one replica node is decommissioned and there is node to move the replica as per VPS

• One of the replica nodes was decommissioned
• During decommissioning, replicas were reduced first
• Replica re-addition failed due to the absence of eligible nodes as defined by the Volume Placement Strategy (VPS) attached to the volume
• Volume is currently running with fewer replicas than originally configured