Get IP from hostname or FQDN using shell scripting

Question

I want to extract IP from Hostname or FQDN using a shell script. If I Ping using the hostname it gives me the IP in the output but how do I extract that from the output to use in my shell script.

Answer 1

This worked for me:

IP1=$(ping -c 1 "$IP" | grep PING | awk -F'(' '{print $2}'| awk -F')' '{print $1}') &> /dev/null

IP being the FQDN

Answer 2

 ip=`nslookup <fqdn> | grep -m2 Address | tail -n1 | cut -d : -f 2`

1. First performs a nslookup.
2. Greps for the first 2 occurrences of the word "Address" - we need any Address after the first since the first one shows the DNS server address used for the lookup.
3. Uses the last one from the grepped output.
4. Splits the line by using the delimiter ":" and extracts the second value.

eg.

$ ip=`nslookup stackoverflow.com | grep -m2 Address | tail -n1 | cut -d : -f 2` && echo $ip
151.101.1.69 

Answer 3

Several ways to do that. Check here.

You may want to use the VARIABLE=$(command) bash syntax. E.g.

IP=$(dig +short index.hu)
echo $IP