Overview

The procedures in this runbook require admin permissions to complete.

Error / Incident

All the ceph monitor nodes are down in the system.

Ceph monitor nodes are the ones acting as entry points for the system, that means that the service is not working and the whole ceph cluster is unusable.

When they go down all the VMs stop having disk access.

Debugging

This might be the result of an ongoing intervention gone wrong, so first try to communicate with the rest of the team and look for any ongoing actions:

Ask on irc (#wikimedia-cloud-admin) if someone is taking any action and forgot about it
Check SAL (or sal.toolforge.org) for host being rebooted/taken down
Check Netbox to make sure the host is not being decommed or network changes were not applied
Check puppet for recent changes that might have affected the node

Then you can continue trying to figure out why the hosts are going down and not coming back up:

Try to ssh to the host
Try to ssh to the management port (see SRE/Dc-operations/Hardware_Troubleshooting_Runbook)

If you got ssh access, you can continue by checking the logs for the monitor service:

root@cloudcephmon1001:~# systemctl status systemctl status ceph-mon@cloudcephmon1001.service

If the ceph cli is working, you can also query the cluster status:

ceph status
ceph health detail

See also Portal:Cloud_VPS/Admin/Runbooks/CephClusterInError in case that the problem is at the application level.

Common issues

Add here any issues you encounter.

Related information

Support contacts

Communication and support

Support and administration of the WMCS resources is provided by the Wikimedia Foundation Cloud Services team and Wikimedia movement volunteers. Please reach out with questions and join the conversation:

Discuss and receive general support

Chat in real time in the IRC channel #wikimedia-cloud ^connect or the bridged Telegram group
Discuss via email after you have subscribed to the cloud@ mailing list

Stay aware of critical changes and plans

Subscribe to the cloud-announce@ mailing list (all messages are also mirrored to the cloud@ list)
Read the News wiki page

Track work tasks and report bugs

Use a subproject of the #Cloud-Services Phabricator project to track confirmed bug reports and feature requests about the Cloud Services infrastructure itself

Read stories and WMCS blog posts

Read the Cloud Services Blog (for the broader Wikimedia movement, see the Wikimedia Technical Blog)

Old incidents

Provide a list of phabricator tasks of previous incidents to be able to more review previous instances of the issue.