Lux In Tenebris - 2013-07-27

Obviously, Fail2Ban SHOULD use day of week and month names only in English as required by RFC (http://tools.ietf.org/html/rfc2822#section-3.3).
As a workaround if you're using fail2ban package in Debian-based distro you may add LANG="en_US" line to your /etc/default/fail2ban to force en_US locale for fail2ban process and get proper timestamps.

Update: The bug was fixed in newer versions.
see "Date in mail is in localized format which cause mail client behave weird" ticket on Github
https://github.com/fail2ban/fail2ban/issues/70

 

Last edit: Lux In Tenebris 2013-07-27