Aria Operations for Logs displays a blank screen in Alert Definitions page

Products

• VCF Operations/Automation (formerly VMware Aria Suite)

Issue/Introduction

UI works normally but when navigating to  Alerts > Alert Definition page it displays a blank screen where the alert definitions should be.

Environment

Aria Operations for Logs 8.18.x

Cause

This issue typically stems from an accumulation of cached session entries in the internal Cassandra database. Specifically, a high record count in the tomcat_sessions table can trigger UI timeouts or significant latency on specific pages.

Resolution

Take a virtual machine snapshot of all nodes in the cluster before proceeding.

To clear out the the tomcat_sessions table:

1. Open an SSH session to the primary node of the Aria Operations for Logs cluster.
2. Log in to the Cassandra database by running the following command: 

   /usr/lib/loginsight/application/lib/apache-cassandra-*/bin/cqlsh-no-pass

3. Check the current number of session records by executing: 

   SELECT COUNT(*) FROM logdb.tomcat_sessions;

    

4. If the count exceeds 2000 records or if the query times out, truncate the table to clear the cache: 

   TRUNCATE logdb.tomcat_sessions;

    
5. To leave the database type:

   exit

    

6. Restart the Loginsight services on all the nodes to apply the changes: 

   service loginsight restart