Safe and Limited Modes
Safe and limited modes are introduced to the cluster environment and standalone nodes.
During clustering operations, in rare scenarios, there can be unrecoverable system errors that can potentially put the cluster or the clustered nodes into unsafe or unstable states. Once in such a state, additional operations or configuration changes can cause the node to crash, the cluster to deform, and the data traffic to be impacted. For example, due to a node attempting to rejoin a cluster, a chassis can end up in a reboot loop. In previous software versions, there was no way to prevent entering the loop.
These modes provide notification, stop further operations from being performed, and give you time to troubleshoot and plan the recovery of the cluster or of any node in the
cluster or standalone node.
Two modes are supported. The first is called safe mode and is triggered when the node detects unrecoverable errors, but the existing flow maps are not impacted. The second is called limited mode and is triggered when the node detects continuous system reboots. In this mode, the node will become standalone and only basic configuration will be allowed.
When a cluster is in safe mode, GigaVUE‑FM displays a Safe Mode banner and message.