1

Topic: Cannot access websites/email from one particular IP

======== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.2
- Linux/BSD distribution name and version: debian 8
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): LDAP
- Web server (Apache or Nginx): apache
- Manage mail accounts with iRedAdmin-Pro? no
- Related log if you're reporting an issue: none
====

Hello,

I have iRedMail running perfectly but today I encountered a strange problem.

Access to the websites I host is blocked for the IP I currently have. Also, I cannot synchronize my mail. Switching to a mobile device/different IP makes it work normally. I CAN connect via SSH though (some custom port).

When I restart "iptables" everything goes back to normal but I will be blocked some time later again.

Fail2Ban is active, but it does not seem that I was blocked by it. The log is empty.

The apache2 log is also of little help here.

# cat /var/log/apache2/error.log
[Mon Aug 31 06:25:16.359738 2015] [:notice] [pid 4862] FastCGI: process manager initialized (pid 4862)
[Mon Aug 31 06:25:16.468927 2015] [ssl:warn] [pid 862] AH01909: server.domain.tld:443:0 server certificate does NOT include an ID which matches the server name
[Mon Aug 31 06:25:16.469475 2015] [wsgi:warn] [pid 862] mod_wsgi: Compiled for Python/2.7.8.
[Mon Aug 31 06:25:16.469498 2015] [wsgi:warn] [pid 862] mod_wsgi: Runtime using Python/2.7.9.
[Mon Aug 31 06:25:16.472868 2015] [mpm_prefork:notice] [pid 862] AH00163: Apache/2.4.10 (Debian) mod_fastcgi/mod_fastcgi-SNAP-0910052141 OpenSSL/1.0.1k mod_wsgi/4.3.0 Python/2.7.9 configured -- resuming normal operations
[Mon Aug 31 06:25:16.472926 2015] [core:notice] [pid 862] AH00094: Command line: '/usr/sbin/apache2'

I found something interesting in "iptables -L": Check the line with "REJECT" in it. IPs and ports have been made anonymous.

# iptables -L
Chain INPUT (policy DROP)
target     prot opt source               destination         
fail2ban-dovecot  tcp  --  anywhere             anywhere             multiport dports http,https,smtp,submission,pop3,pop3s,imap2,imaps,sieve
ACCEPT     all  --  anywhere             anywhere             state RELATED,ESTABLISHED
ACCEPT     all  --  anywhere             anywhere            
ACCEPT     icmp --  anywhere             anywhere             icmp echo-request
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:17XXX
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:http
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:https
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:smtp
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:submission
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:pop3
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:pop3s
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:imap2
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:imaps

Chain FORWARD (policy DROP)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         

Chain fail2ban-dovecot (1 references)
target     prot opt source               destination         
REJECT     all  --  pXXXXXXXX.dip0.t-ipconnect.de  anywhere             reject-with icmp-port-unreachable
RETURN     all  --  anywhere             anywhere  

Why is the IP banned? I am quite certain that I did not have any false logins. Also, the fail2ban log is empty.

Thanks in advance!

----

Spider Email Archiver: On-Premises, lightweight email archiving software developed by iRedMail team. Supports Amazon S3 compatible storage and custom branding.

2

Re: Cannot access websites/email from one particular IP

It's blocked in chain 'fail2ban-dovecot', that means it's caused by error of IMAP/POP3 service.
And there must be some log of Fail2ban when it banned this client.

3

Re: Cannot access websites/email from one particular IP

Ok, some login was actually faulty. Password was wrong.