In SearchStax, a 503 Updates are Disabled Error means that Zookeeper has blocked updates because a Solr node has failed.
2023-05-31 17:05:20,059 ERROR - received unexpected error status from server: 503 ({"responseHeader":{"status":503,"QTime":588},"error":{"msg":"Cannot talk to ZooKeeper - Updates are disabled.","code":503}}
In one instance, a node failed after running for fifteen minutes at a load of 100. (The maximum sustainable load for this node was 8.)
The swap memory was completely utilized, causing the node to become unresponsive.
In this instance, SearchStax engineers had to restart the nodes one-by-one to resynchronize the indexers. Updates were suspended temporarily, but query service was not disrupted.
Questions?
Do not hesitate to contact the SearchStax Support Desk.