There is currently an incident, and database servers 11, 22 and 23 stopped responding. Instances using those servers are down. I apologize for the disruption. I'm trying to gather more information and will update as soon as I know more.
OK, the problem has been identified in the data center: https://bare-metal-servers.status-ovhcloud.com/incidents/dgksqhl6lswj
[GRA4][Dedicated Servers] - Rooms GRA0404 - GRA0406 incident notification

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Database server 23 is responding again.
Database servers 11 and 22 still down.
Database server 11 is now also back online. Only database 22 still down.
@mastohost Should the checkmarks on https://status.masto.host/ be updating? They all show green despite the outage
@noelle the servers are still sending out the Heartbeat Monitor that's why it's green. Ideally, they shouldn't be green, but https://360monitoring.com/ reports them as up as long as there is a heartbeat being sent.
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@mastohost Ah yes, sometimes I have built a health check which includes a call to database, redis, and anything else essential. No idea about the details of doing that with Mastodon and 360monitoring, though. @noelle