fail2ban chain on demand

 The iptables actions in v.0.10 create chains on demand (i. e. by first ban of some IP, corresponding its IP-family), see #1742 for more info.

If you don't want it, use action = iptables-multiport[..., actionstart_on_demand=false] in your jail.local resp. actionstart_on_demand = false in definition section of your action.d/iptables-multiport.local.

https://github.com/fail2ban/fail2ban/issues/1755