Problems with Thunderbird (Linux Mint) & Firewall

Community Support Firewall
1

Hello,

My email client installed on Linux Mint (Thunderbird) constantly causes a ban on the HestiaCP firewall.

I accessed HestiaCP and added my IP address to the whitelist. I added my country.

I accessed the server’s SSH and added my IP address to Fail2ban.

I restarted.

After a few hours, my IP address is banned again. I have to log into the Panel and remove the ban to check my email. I also use Mailnag on my Linux Mint to get notifications when Thunderbird is not running.

If my IP address is on the whitelist, why is it banned? I don’t understand.

11
111066×1380 117 KB

2

Hi,

iptables rules are read sequentially, and the rules to DROP your IP are located before your ACCEPT rule. You chan check it:

iptables -S

You should figure out why fail2ban is repeatedly triggering a firewall rule to block your ip.

For now, you could add your ip to the whitelist in /etc/fail2ban/jail.d/whitelist.local so fail2ban will ignore it.

Create the file /etc/fail2ban/jail.d/whitelist.local with this content:

[DEFAULT]
ignoreip = here.your.ip

Restart Fail2Ban to apply the change.

systemctl restart fail2ban

But as I said, you should check the logs to understand what’s going on with your IP:

grep 'HereYourIP' /var/log/fail2ban.log
grep 'HereYourIP' /var/log/dovecot.log
grep 'HereYourIP' /var/log/exim4/mainlog
2 Likes
3

Thank you very much for your help. It seems this has worked for now, and my IP can access the email without getting banned every five minutes. However, I had to restart my router, which caused my IP to change, so I had to repeat the process all over again. I’m concerned about having to do this every time my router gets a new IP. Is there a more reliable option? Something like… instead of whitelisting my IP, perhaps allowing the router’s ID or something similar? I also ran the commands you mentioned, but there were so many results that I had to record a video. I’m sending it to you via private message since it contains sensitive data. Thanks again for your assistance.