edit
/etc/fail2ban/jail.conf
“ignoreip” can be an IP address, a CIDR mask or a DNS host. Fail2ban will not ban a host which matches an address in this list. Several addresses can be defined using space separator.
ignoreip = 127.0.0.1/8 173.245.48.0/20 103.21.244.0/22 103.22.200.0/22 103.31.4.0/22 141.101.64.0/18 108.162.192.0/18 190.93.240.0/20 188.114.96.0/20 197.234.240.0/22 198.41.128.0/17 162.158.0.0/15 104.16.0.0/12 172.64.0.0/13 131.0.72.0/22