Level: Critical
Purpose: The EMS will create a STOMP queue in RabbitMQ where handles the updates for the EMS Frontend GUI. The queue should live for as long as the EMs tab exists.
This queue binds to the 'ems_push_notification_topic' exchange with the routing key 'AlarmCacheUpdate' so anything pushed onto this exchange with that binding key the frontend will obtain. The frontend takes the Alarm Cache Update Message and converts it to an AlarmCacheDTO (GWT JSON to Java Object - Implementation of Interfaces). This object is then fired as a GWT event so GWT code can subscribe to the event.
The the naming of these queues is stomp_subscription_*some random characters*
GWT communicates with the stomp plugin for RabbitMQ which runs on the loadbalancer server.
Scenario: A stomp queue has potentially not auto-deleted and messages in queue has been >=800 for 120s.
Resolution: Manually delete the STOMP queue as its likely not needed any more.
If the EMS is using HTTPS, then it will be via the loadbalancer. If it is not using HTTPS, and instead using HTTP, then it is via the server RabbitMQ is hosted on.
For example to connect to rabbitmq on ExteNet:
https://extlb.ext:15672/#/queues
or
http://extapps2.ext:15672/#/queues
Check this sheet to see which servers are hosting a RabbitMQ https://docs.google.com/spreadsheets/d/1Ebj0kWPl63Q4L3f_oo_kvWoh5ZRq2vFI8FmrWbjoPlo/edit#gid=1762968851
Manual Action Steps: See http://wiki.err/doku.php?id=development:applications:alarmcache:works
Connect to the rabbitmq admin panel using one of the links above. Sign in. The credentials are in PWSafe
In the queues tab, you will see the stomp_subscription_*random_characters* queue.
Click that, scroll down to Delete and then delete it.
Auto Clear: