ElasticSearch Error MasterNotDiscoveredException

[abnerlusung]

Hi Dynatrace community,

We need your help on how to fix the MasterNotDiscoveredException on ElasticSearch.  Please see attached.

We are using Dynatrace Managed 1.268.145 with 3 cluster nodes.

The scenario yesterday, I updated the /etc/fstab to keep the EFS mount then performed the Stop/Start of instance.

The Dynatrace Server failed with the error MasterNotDiscoveredException.

Then using ElasticSearch Health Check returned MasterNotDiscoveredException.

The command is : curl <ip_address>:9200/_cluster/health 

Regards,

Abner

[Radoslaw_Szulgo · Accepted solution]

Usually this might indicate some network problems between cluster nodes. At the beginning try to perform a rolling restart of nodes. If that doesn't help - please investigate elasticsearch logs or contact our Dynatrace support team.