Email templates have disappeared and not available in the pull down for alerts

[bpennin]

We’re running RHEL 8 with the latest Nagios Log Server 2026 release. After the upgrade, OpenSearch initially started without issues, and we were able to create and use email templates. A few days later, the email templates disappeared from the interface. We attempted to troubleshoot by restarting the cluster, but it failed to come online due to OpenSearch not starting because of a missing JAR file. We removed the reference to that JAR file, which allowed the cluster to start and run normally—except we still cannot create or view email templates in the Alerting tab. We’ve tried clearing the cache and restarting both the server and the instance without success.

[jmichaelson]

We have a fix for the upgrade issue and are hoping it will be in the next release of Log Server. Keep an eye out for change log item NLS#801.

As for the email templates disappearing, is there anything else you're seeing has disappeared? Logs, etc.?

[bpennin]

No, just templates and the email drop down where you select the template for the alert is blank.

I had a copy of the /usr/local/nagioslogserver directory backed up prior to the date of us losing the email templates. We restored that this past Friday afternoon and everything was working again(email templates) could be created and used. After a few days we are back to where we cant create or see them. Hope this helps.

[bpennin]

We have a fix for the upgrade issue and are hoping it will be in the next release of Log Server. Keep an eye out for change log item NLS#801.

As for the email templates disappearing, is there anything else you're seeing has disappeared? Logs, etc.?

Could you provide some details on what NLS#801 will change or fix and how it may impact existing configurations? thanks!!!

[bpennin]

Still need an answer or work around for the email templates disappearing and the drop downs being blank for them?

[bpennin]

We have a fix for the upgrade issue and are hoping it will be in the next release of Log Server. Keep an eye out for change log item NLS#801.

As for the email templates disappearing, is there anything else you're seeing has disappeared? Logs, etc.?

We have not noticed anything else missing from the server, do you have suggestions for the email templates disappearing?

[jmichaelson]

I've got a bunch of questions for you:

You mentioned a cluster.

How many instances do you have in it?
Is OpenSearch running on all of them?
If not, what happens when you run systemctl start opensearch on the ones that aren't running?
How is the disc space situation on your instances?

I'm wondering if you're in a situation where a disc got past a safety threshold (internal to OpenSearch) and OpenSearch stops (write) access because of that (and Nagios Log Server isn't handling failure responses from OpenSearch gracefully). If multiple instances ended up in a not running state, its possible that your email templates are stored on the instances that are down and thus inaccessible.