I'm facing a problem with a Linux webserver of mine. It's a VM Ubuntu 10.4 LTS which runs a Wordpress network site. Out of the blue with no changes being made on the back end, ftp has stopped as has ssh. In addition, I cannot reach the host/site at all, but I can successfully ping it from inside the network... Similarly, I can do an nslookup just fine.
I'm very perplexed as to what's wrong. Below's a table of what's ok, which I hope might be useful to helpers.
Nslookup YES
Ping YES - Only within network
FTP NO
SSH NO
HTTP NO - Apache, Mysql "appear" to be running fine though
Other Servers YES
on Cluster ok
Ports open YES - listening on all the necessary: 80, 22, 23, 25, 3306 etc.
Telnet ??? - Ports 80, 3306 don't work, others do
From the above I've gathered it's to do with my box, well that was obvious, but seeing that DNS resolution is ok (internally at least) and how random services have gone down, I'm wondering if there has been some kid of bug or virus, or if the networking just broke out of the blue.
Many, many thanks in advance!
netstat -rnandnetstat -tnlp? – Arcege Mar 22 '12 at 19:38ping, which runs over ICMP, whileftprelies on UDP and both HTTP and ssh rely on TCP. I remember reading that connection tracking iniptablesmay cause legitimate requests to be dropped, but I doubt this is related at all. – njsg Mar 22 '12 at 21:36