Check IP address blacklist status in Bash

Here is a Linux Bash shell script to check whether an IP address is listed in a DNSBL blacklist, or RBL. Using this script in Bash you can quickly test if an IP address is blacklisted.
Here is a Linux Bash shell script to check whether an IP address is listed in a DNSBL blacklist, or RBL. Using this script in Bash you can quickly test if an IP address is blacklisted.