The Telescope Web home page sometimes stops loading and displays the error message
No instance available instead of displaying the page. This happens if none of the TSWeb workers are available to respond because they crashed and were unable to restart, and this can be established with the presence of the following error message in TSWeb logs:
[YYYY-MM-DD HH:MM:SS UTC] <WorkerThread30> !!! Request will be REDIRECTED to non-refusing instance </Scripts/WebObjects.dll/TSWeb.woa> ... [YYYY-MM-DD HH:MM:SS UTC] <WorkerThread25> !!! Request will be REDIRECTED to non-refusing instance </Scripts/WebObjects.dll/TSWeb.woa/wa/SamlDirectAction>
Agents should perform the following actions on the App instance. Additionally, also create a ticket on PLNP JIRA of type SaaS Problem and priority Showstopper to configure monitoring for similar situations in the future if it doesn't exist. PLNP-5844 is one such example.
If all the TSWeb workers have crashed, which could be validated by looking at the log files of the workers, then:
- Restart all the TSWeb workers.
- Restart IIS.
Once the TSWeb workers are restarted, check that accessing TSWeb is showing the Telescope home page as expected.