[OVH] Complete server crash for no apparent reason

[crhampus]

So I couldn't access my webmail due to "database connection error" and so I decided to restart my server.
Now I can't even access the normal panel, I get the following error:

Critical Error: [0100] - Unable to connect or authenticate to the Sentora database (sentora_core).
We advice that you contact the server administrator to ensure that the database server is online and that the correct connection parameters are being used.

My best guess is that there is some sort of problem with the MySQL Database but I have no idea on how to solve it.

Has anyone else experience a problem like this and found a solution?


EDIT: Also, I can't even connect via ssh, I get the error "connection reset by peer".

Something seems to be seriously problematic here...

FINAL EDIT: See my last reply for full documentation.
TL;DR: My server was being attacked which I didn't realise, effectively shutting down most services.
So a tip if you're in the same situation: check your log files for unwanted "guests" on your system.

[apinto]

Are you using OVH?

[crhampus]

Are you using OVH?

Yes, in fact I am

Are you telling me there is a major issue with OVH right now or is it more of a general issue with OVH and Sentora?

[apinto]

There are some issues with OVH today.
I had the same a few hours ago.
http://status.ovh.es/

[apinto]

Could be that... or maybe not.
Try to restart the VPS using OVH panel, if it stucks at 20%, its OVH issue.

[crhampus]

Yes, it was OVH
Working as it should now, though not sure for how long.

Guess that's what you get for buying a cheap service such as OVH.
But, at least it works well most of the time!

[apinto]

OVH has not failed me.
Every host has their downtimes.
Just be very careful with the lack of auto backups.
Make sure you backup on your own.

[crhampus]

Update: Seems like OVH wasn't completely to blame after all.
Apparently some chinese hacker(s) seemed to have gotten a hold of my server with no fail2ban installed and started a relentless DDoS/DoS attack trying to login over SSH.
This seems to be what caused an overload on the server, effectively shutting down all external services except for apache, which explains why my sites would still load completely fine.

Well, all's well that ends well I guess, no real harm done and everything is now back to normal

So if anyone stumbles upon a similar issue, I would suggest looking at your log files to see if anyone is trying to access your server.