The server works exactly day and tightly falls. With what can be connected?

Question

Debian

Good afternoon.
Server at OVH. Debian 10 + ISPmanager.
Works exactly day and tightly falls. Doesn't even ping.
The load does not grow, the memory is not clogged.
It looks like the network cable has just been pulled out.
After a reboot from the OVH panel, everything is restored and works again EXACTLY a day.
Where to dig, what can be connected with?

Answer 1

in fact, I advise you to run away from OVH quickly and smartly: they host some kind of cool-hacker evil spirits, they bombed my servers with brute force, injections and other script-kiddisney. TP does not itch at all, I had to take and ban all subgrids (AS) of this dip.
Why does the server run away exactly in a day? Well, it's clear - cron is launched and kills some setting. for example binding IP to the server. Well, then the boy gets into ssh and writes ifconfig with handles)
Terrible prov, worse than Hostgator and all sorts of Bluehosts)