Fail2Ban fails to ban

MET
Joined: Sat 14 of May, 2005

Fail2Ban fails to ban

Posted:Sun 23 of May, 2010 (06:22 UTC)
For my trials to get Fail2Ban work I had the jail.conf parameters set for manual testing to:

maxretry = 3
findtime = 300
bantime = 600

During this time I happened to receive an attack on my asterisk. Fail2ban noticed the attack but didn't ban the IP. The logs show the following:

Asterisk:

[2010-05-22 16:04:05] NOTICE[29225] chan_sip.c: Registration from '"1249349713"<sip:1249349713@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:04:05] NOTICE[29225] chan_sip.c: Registration from '"100"<sip:100@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:04:05] NOTICE[29225] chan_sip.c: Registration from '"101"<sip:101@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:04:05] NOTICE[29225] chan_sip.c: Registration from '"102"<sip:102@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:04:05] NOTICE[29225] chan_sip.c: Registration from '"103"<sip:103@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:04:05] NOTICE[29225] chan_sip.c: Registration from '"104"<sip:104@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
....
[2010-05-22 16:12:58] NOTICE[29225] chan_sip.c: Registration from '"9994"<sip:9994@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:12:58] NOTICE[29225] chan_sip.c: Registration from '"9995"<sip:9995@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:12:58] NOTICE[29225] chan_sip.c: Registration from '"9996"<sip:9996@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:12:58] NOTICE[29225] chan_sip.c: Registration from '"9997"<sip:9997@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:12:58] NOTICE[29225] chan_sip.c: Registration from '"9998"<sip:9998@12.34.56.78>' failed for '76.76.96.74' - No matching peer found
[2010-05-22 16:12:58] NOTICE[29225] chan_sip.c: Registration from '"9999"<sip:9999@12.34.56.78>' failed for '76.76.96.74' - No matching peer found


Fail2Ban:

2010-05-22 16:04:06,632 fail2ban.actions: WARNING [asterisk-iptables] Ban 76.76.96.74
2010-05-22 16:04:09,130 fail2ban.actions.action: ERROR printf %b "Hi,\n
The IP 76.76.96.74 has just been banned by Fail2Ban after
11 attempts against ASTERISK.\n\n
Here are more information about 76.76.96.74:\n
`whois 76.76.96.74`\n
Regards,\n
Fail2Ban"|mail -s "[Fail2Ban] ASTERISK: banned 76.76.96.74" Me@My.net returned 7f00
2010-05-22 16:04:09,130 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:04:10,133 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:04:11,132 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:04:12,132 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:04:13,132 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:04:14,132 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:04:15,133 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:04:16,133 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:04:17,133 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
...
2010-05-22 16:12:55,309 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:12:56,311 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:12:57,318 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:12:58,321 fail2ban.actions: WARNING [asterisk-iptables] 76.76.96.74 already banned
2010-05-22 16:14:07,356 fail2ban.actions: WARNING [asterisk-iptables] Unban 76.76.96.74


The attack makes about 40 attempts per second whereas fail2ban logs only each second "already banned" but fails to block the attack.


Questions:

Any ideas why fail2ban failed to ban this IP ?
Why Fail2Ban can't send the mail to a valid address which has been changed here to "Me@My.net". Could the reason be that the mail account is on a different server?