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THpubs
Asked: 2012-08-29 23:00:12 +0800 CST

Fail2Ban adds iptable rules but they are not working?

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Fail2Ban just blocked my IP for 3 SSH attempts. It added the iptables rule and I can see it using the "sudo iptables -L -n" command. But I can still access the site and login through SSH! What might be the problem? Is it because im using CloudFlare? I have set Nginx to write the real IPs to the access logs instead of the Cloud Flare IP. Isn't it enough?

Chain fail2ban-ssh (1 references)
 target     prot opt source               destination         
 DROP       all  --  119.235.14.8         0.0.0.0/0           
 RETURN     all  --  0.0.0.0/0            0.0.0.0/0

The input chain :

Chain INPUT (policy DROP)

    target     prot opt source               destination         
    fail2ban-NoAuthFailures  tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:80
    fail2ban-nginx-dos  tcp  --  0.0.0.0/0            0.0.0.0/0            multiport dports 80,8090
    fail2ban-postfix  tcp  --  0.0.0.0/0            0.0.0.0/0            multiport dports 25,465
    fail2ban-ssh-ddos  tcp  --  0.0.0.0/0            0.0.0.0/0            multiport dports 22
    fail2ban-ssh  tcp  --  0.0.0.0/0            0.0.0.0/0            multiport dports 22
    ufw-before-logging-input  all  --  0.0.0.0/0            0.0.0.0/0           
    ufw-before-input  all  --  0.0.0.0/0            0.0.0.0/0           
    ufw-after-input  all  --  0.0.0.0/0            0.0.0.0/0           
    ufw-after-logging-input  all  --  0.0.0.0/0            0.0.0.0/0           
    ufw-reject-input  all  --  0.0.0.0/0            0.0.0.0/0           
    ufw-track-input  all  --  0.0.0.0/0            0.0.0.0/0           
    LOG        all  --  0.0.0.0/0            0.0.0.0/0            LOG flags 0 level 4
fail2ban

1 Answers

  1. Best Answer

    UPDATE 2019: The API use in origin answer has been deprecated in favor of API v4, use new version instead. Fail2ban unban action fails with Cloudflare thanks @baptx commented

    iptables can not get the real ip, so you should use cloudflare's api to blacklist the IP on the cloud.

    here is my action config file

    # Fail2Ban configuration file
#
# Author: Charles Chou
# Modified: Norman Yee 
#           fix original cloudflare-blacklist.conf

# $Revision$
#

[Definition]

# Option:  actionstart
# Notes.:  command executed once at the start of Fail2Ban.
# Values:  CMD
#
actionstart =

# Option:  actionstop
# Notes.:  command executed once at the end of Fail2Ban
# Values:  CMD
#
actionstop =

# Option:  actioncheck
# Notes.:  command executed once before each actionban command
# Values:  CMD
#
actioncheck =

# Option:  actionban
# Notes.:  command executed when banning an IP. Take care that the
#          command is executed with Fail2Ban user rights.
# Tags:    <ip>  IP address
#          <failures>  number of failures
#          <time>  unix timestamp of the ban time
# Values:  CMD
#
actionban = curl -s "https://www.cloudflare.com/api.html?a=ban&key=<ip>&u=<account>&tkn=<token>"

# Option:  actionunban
# Notes.:  command executed when unbanning an IP. Take care that the
#          command is executed with Fail2Ban user rights.
# Tags:    <ip>  IP address
#          <failures>  number of failures
#          <time>  unix timestamp of the ban time
# Values:  CMD
#
actionunban = curl -s "https://www.cloudflare.com/api.html?a=nul&key=<ip>&u=<account>&tkn=<token>"

[Init]

# Option:  account
# Notes.:  In the actionban and actionunban sections,replace CLOUDFLARE_LOGIN with your CloudFlare login email
# Values:  your CloudFlare account
#
account = [email protected]

# Option:  token
# Notes.:  In the actionban and actionunban sections, replace CLOUDFLARE_API_TOKEN with your API key
# Values:  Your CloudFlare API key 
#
token = Your API key here
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