What Do I Do If My Cluster Status Is Unavailable?

Symptom

A CSS cluster status is Unavailable.

Figure 1 Unavailable cluster

Cause Analysis and Solution

• If the task status is Frozen, see A Cluster Is Frozen and Unavailable.
• If task status is Configuration error. Restart failed, see What Can I Do If My Custer Is Unavailable Due to an X-pack Parameter Configuration?.
• If the node error log "master not discovered or elected yet, an election requires at least 2 nodes with ids [xxx, xxx, xxx, ...], have discovered [xxx...] which is not a quorum" is displayed, see A Cluster Is Unavailable Due to Improper Security Group Policy.
• If the node error log "fatal error in thread [main], exitingjava.lang. NoClassDefFoundError: xxx/xxx/.../xxxPlugin at ..." is displayed, see A Cluster is Unavailable Due to Plugin Incompatibility.
• If the cluster health status is red and the value of unassigned shards is not 0, the cluster has index shards that cannot be allocated. For details, see A Cluster is Unavailable Due to Improper Shard Allocation.
• If a cluster is unavailable after being restored or migrated, see A Cluster is Unavailable Due to Incompatible Data Types.
• If the node error log "OutOfMemoryError" and warning information "[gc][xxxxx] overhead spent [x.xs] collecting in the last [x.xs]" are displayed, see A Cluster is Unavailable Due to Heavy Load.