I have a problem with a Debian based Server, unfortunately housed in a remote location. Two days ago, it was suddenly down and completely unreachable. After having someone reboot it, it worked for about a day, then seemed to be down again.
This time, however, it was different:
-The server reacts to pings
-It is scannable, and all the relevant ports are open But:
-Open shells were immediately blocked, and no warning had been shown
-It's not possible to open any connection - the TCP/IP handshake seems to have some problems:
As this is a private server of a small community, we don't have the resources to pay a technician to fix the problem for us, so any hints how to fix the problem after the next reboot would be highly appreciated...