I am using this simple command to monitor connections (to deal with some recent DOS attacks) on my Debian server:
netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
How do I run it continuously? So it will refresh itself once per minute (or any given amount of time, of course). I tried watch:
watch -n 30 "netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n"
But it changed the output from nice list with num of connections to smth like this:
1 tcp 0 10015 [LOCAL IP]
...
1 Proto Recv-Q Send-Q Local Address Foreign Address State
1 Active Internet connections (w/o servers)
So external IP is not being displayed... Is there's something I missed?
EDIT: This is how the original output looks:
2 [IP ADDRESS]
4 [IP ADDRESS]
4 [IP ADDRESS]
4 [IP ADDRESS]
7 [IP ADDRESS]
16 [IP ADDRESS]
71 [IP ADDRESS]
And when I say [LOCAL IP] - I mean my machine's IP.
EDIT 2: Forgot to add - it just freezes when I run it with -c.