Shell Programming and Scripting

Hello everyone,

I have written a one liner which looks in a configuration file for remote hosts to connect to. It then resolves them by first ping, and nslookup if it fails, then places the info in the hosts file.

The whole thing works, seemingly, apart from one slight issue. I would like to filter out remote hosts which are already specified as IP addresses, since it is obviously unnecessary to resolve them. I am learning sed slowly, but can anyone help achieve this?

Here is the script currently

Code:

cat connect.conf | grep "remote " | awk '{print $2}' | cut -d : -f1 | sort | uniq | while read SRV ; do if ! grep $SRV /etc/hosts ; then IP=$(ping -c 1 $
SRV | grep "64 bytes from " | awk '{print $4}' | cut -d : -f1) ; if [ $IP == "" ] ; then IP=$(nslookup host $SRV | grep Server: | awk '{print $2}') ; fi ; if [ $IP != "" ] ; then echo $IP 
$SRV >> /tmp/hosts; fi ; fi ; done

I think that this following sed command is useful for placing after uniq or after the first cut command, however I believe it needs altered

Code:

sed 's/[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}//'

Can anyone assist in this? Any help would be appreciated!

Edit: Fixed it, silly me

Code:

grep -Ev '([0-9]{1,3}\.){3}[0-9]{1,3}'