fail2ban/fail2ban — pull request #462 by grooverdan (2013-11-28 12:23:15+00:00)
Title: DOC: document rational behind 20 character jail name limit

took a bit of finding but from #222 the chain limit is 30 but "fail2ban-" is used in the creation of chains so 20 is reasonable. Better document this.

http://blog.yo61.com/length-limit-to-iptables-chain-names/