Existe um cliente fail2ban:
# fail2ban-client set <JAIL> banip <IP>
# fail2ban-client set <JAIL> unbanip <IP>
Exemplo:
# fail2ban-client set example banip 10.10.1.1
10.10.1.1
# fail2ban-client status example
Status for the jail: example
|- Filter
| |- Currently failed: 0
| |- Total failed: 10
| '- File list: /var/log/example.log
'- Actions
|- Currently banned: 1
|- Total banned: 2
'- Banned IP list: 10.10.1.1
# fail2ban-client set example unbanip 10.10.1.1
10.10.1.1
# fail2ban-client status example
Status for the jail: example
|- Filter
| |- Currently failed: 0
| |- Total failed: 10
| '- File list: /var/log/example.log
'- Actions
|- Currently banned: 0
|- Total banned: 2
'- Banned IP list: