[CentOS] fail2ban problems - not banning

Wed Jan 6 10:57:20 UTC 2021
Gary Stainburn <gary.stainburn at ringways.co.uk>

Hi everyone,

I've got fail2ban and firewalld set up on a C7 box, in theory protecting 
dovecot, exim and ssh but I'm not convinced it's doing anything.

in /var/log/fail2ban.log I'm getting loads of entries such as:

2020-12-22 19:08:08,100 fail2ban.actions        [1836]: WARNING 
[dovecot] 78.128.113.67 already banned

I think this is because the actual ban is not working.  I have entries 
such as:

2020-12-22 19:38:27,619 fail2ban.utils          [1836]: ERROR 
7f119e95f7f0 -- exec: ports="0:65535"; for p in $(echo $ports | tr ", " 
" "); do firewall-cmd --add-rich-rule="rule family='ipv4' source 
address='113.110.47.81' port port='$p' protocol='tcp' reject 
type='icmp-port-unreachable'"; done
2020-12-22 19:38:27,619 fail2ban.utils          [1836]: ERROR 
7f119e95f7f0 -- stderr: 'Error: INVALID_PORT: 0:65535'
2020-12-22 19:38:27,619 fail2ban.utils          [1836]: ERROR 
7f119e95f7f0 -- returned 102
2020-12-22 19:38:27,620 fail2ban.actions        [1836]: ERROR Failed to 
execute ban jail 'dovecot' action 'firewallcmd-rich-rules' info 
'ActionInfo({'ip': '113.110.47.81', 'fid': <function <lambda> at 
0x7f119f084050>, 'family': 'inet4', 'raw-ticket': <function <lambda> at 
0x7f119f0845f0>})': Error banning 113.110.47.81

I've done some Googling and received lots of responses about fail2ban 
failures but I can't find anything relating to this.

Anyone got any ideas?