I cant access my webserver from several IP adress. And i think the problem might be in iptables.
I have fail2ban installed on a server and maybe that is the reason.
My webserver runs under ubuntu 13.10
IPTABLES -L gives me the next:
root@mail:/home/irishman# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
fail2ban-postfix tcp -- anywhere anywhere multiport dports http,https,smtp,submission,pop3,pop3s,imap2,imaps,sieve
fail2ban-dovecot tcp -- anywhere anywhere multiport dports http,https,smtp,submission,pop3,pop3s,imap2,imaps,sieve
fail2ban-roundcube tcp -- anywhere anywhere multiport dports http,https,smtp,submission,pop3,pop3s,imap2,imaps,sieve
fail2ban-ssh tcp -- anywhere anywhere tcp dpt:ssh
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain fail2ban-dovecot (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain fail2ban-postfix (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain fail2ban-roundcube (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain fail2ban-ssh (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
I can't see any banned adress there. But the problem remains. I can access my server with one internet provider and can't with another.
Also i have calmAV installed(can it be the reason?)
As you say, it looks like fail2ban isn't your problem. Just to check, try stopping the fail2ban service (service fail2ban stop) temporarily, which will remove any iptables restrictions in place, and see what happens.
The next thing to try is traceroute from some of the hosts that can't reach the server, and see if there's a common place where they get stuck - you can occasionally get routing problems, especially if your web server is on a recently-allocated block of IP addresses.