There are various reasons for replication failure and I analyzed these issues when I was working on activation and deactivation of the pages. There are different cases for replication queue;
(1) Your replication queue is blocking and you have no idea why is it not getting processed;
(2) Someone accidentally activated thousands of pages and you want to clean them now;
(3) You want a safe way to remove replication jobs and then activate them again if require and
(4) You want to clean a dummy replication agent.
How to analyze/Check Replication issues:
1. Check the replication queue status:
Active: when pages have been activated successfully (color: Green)
Idle: when the queue is empty.
Pending: When publication is in queue (color:Yellow)
Blocked/ Failed: when items are in the queue, but cannot be processed (color: Red)
2. Review the replication agent level issues at http://host:port/etc/replication/agents.author/AgentName.log.html#end.
- Sometimes replication queue is blocked due to issues with a single or more items in the replication queue. In that scenario, when you go to replication queue- it says “Queue is blocked”.
- Open the replication log via “View Log” link and check when last replication attempt was successful. Try to clear first item in replication queue, see if it unblocks replication queue.
- Verify connectivity with publish instance by clicking “Test Connection”.
- Click on edit and check whether an agent is enabled? Ensure it is enabled, verify Transport details e.g. publish server URL, username, password, verify trigger tab, ignore default option should be unchecked unless this agent is being used for replication via backend process.
Also, go to CRX Content Explorer, and ensure that there is no /bin/receive node on the publish and author instance. Otherwise, delete it.
3. If the replication queue is in “idle” state and none of the above applies, in this case, the problem is most likely caused by workflows. If the workflows are not being processed then replication item never gets to replication queue. To monitor status of your workflows, you can check workflow dashboard to check number of running workflow instances.
4. Replications slows down when system is under high load or is experiencing other performance issues.