Why does the server on Selectel suddenly stop responding?

Question

System administration

Hello!

I encountered a strange problem on the Selectel server - sometimes the server stopped responding to all requests from the network (pings, http, ssh), only a restart from the selectel panel saved it (the kve terminal did not work there either), while judging by the logs during unavailability, it continued work honestly.
There was nothing interesting or unusual in the syslog.
On the server itself, elementary gosh applications were running in the form of systemd services (at first I was afraid that the logs were overflowing, but their restriction did not save), an ipsec tunnel for an external api and small postgres with a rebbit. Those support makes a helpless gesture and says that they didn’t find anything wrong.

Now the server has gone into complete silence, even restarts do not save.

I would be glad for any ideas in which direction to look for the problem, thanks in advance!

Answer 1

You are not asking a toaster about this, but a support selector

Answer 2

Good afternoon. Nothing just happens:
1) Remember at what point in time you first discovered the problem. Now remember what work was being done at that point in time?
2) Monitor the frequency of the problem. If problems occur with a stable frequency (for example, once a day at midnight) - this is a hook, look for what is happening in the system at that time (for example, some process is started by the crown).
3) "Cut off the excess." This is a long time to do after paragraph 1.2. If you can’t talk about the full performance of the service now, then turn off all your services in sequence until the problem disappears.
So you will be able to identify the problem, and this is already half the battle.

Answer 3

You can try to see the state of the server at the time of the problem through the KVM console, it should work (if it doesn't work, kick the support).
If only the network falls off, then I would update the network card driver from the manufacturer's website, distributions usually do not have the latest firewood.

Answer 4

If at the moment the server is running and there is access to it, we look at the logs and think.
If the server is not available at the moment, we kick the hoster's technical support.