Can fail2ban-client tell me if an ip from a CIDR range is in a jail? [duplicate]
Solution 1:
There is a nifty little tool grepcidr that is useful for quick shell scripts that need to find matches from a specific CIDR in a list with IPv4 or IPv6 addresses.
sudo iptables -L -n | grepcidr "13.54.63.128/26"