Questions tagged [fail2ban]

Fail2ban scans log files (e.g. /var/log/apache/error_log) and bans IPs that show the malicious signs -- too many password failures, seeking for exploits, etc.

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sshd LogLevel not working

there Someday, my ubuntu(22.04) machine write auth.log too short. Following auth.log can't recognize from fail2ban(sshd) Mar 6 17:52:03 laphs sshd[13792]: pam_unix(sshd:auth): check pass; user ...
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Fail2ban with lots of IPs in log

I have a VPS with Ubuntu 20.04 to run a Counterstrike source server and I'm experiencing a weird kind of attack on ssh (brute force?) I setup fail2ban and on the first day of server online a lot of ...
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Fail2ban sshd rule is active but not working!

I used ubuntu 22.04 TLS. sshd_config: Port 9401 SyslogFacility AUTH LogLevel VERBOSE MaxAuthTries 3 /etc/fail2ban/jail.local: [ssh-9401] enabled = true filter = sshd logpath = /var/log/auth.log ...
Yaraa's user avatar
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2 votes
1 answer
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Fail2Ban bans, iptables lists the block but connection is still not blocked

I am using Ubuntu 22.04 LTS and I am trying to prevent repeated connection attempts to our mail server using fail2ban. Fail2ban creates a proper entry in the iptables configuration, but the related IP ...
Deckard's user avatar
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Fail2ban will not start

I installed Fail2ban but i can start the service. Every time i get this Error: systemctl status fail2ban × fail2ban.service - ...
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Using sendmail to send notifications (Fail2Ban) through Postfix relay

I'm still pretty much a complete neophyte when it comes to Ubuntu/Linux in general, but I'm familiar with how sending mail via SMTP works in general. So now I currently have two Ubuntu servers running ...
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Easy Desktop Remote with Xubuntu, Android and Fail2ban protection

I have switched from Windows to Xubuntu 22.04 last days and now i am searching some easy setup for desktop remote. The years before I always used Windows RDP which was not so easy. Windows did not ...
user6266369's user avatar
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Fail2ban needs restart before running on ubuntu 22.04

I am running since today fail2ban on ubuntu 22.04 with ipv6 and when i start ubuntu the logs says every time i booting: 2023-04-21 23:43:39,740 fail2ban.server [1662]: INFO Shutdown in ...
user6266369's user avatar
-1 votes
1 answer
267 views

blocking bot attacks ufw fail2ban

Im doing something dumb, or missing something. Can anyone spot it please? I have a tplink archer C7 set to port forward from an external port to port 22 on my internal server for ssh. But I still see ...
colic's user avatar
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How to monitor and protect machine

Recently I've been locked out of my Ubuntu as a precaution and was notified that my vps/dedi was used for DDoS attacks on other services within the host as well as outside the host. I've been granted ...
Nemanja Rankovic's user avatar
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2 answers
506 views

Fail2Ban, ban all ip except for myself

I am trying to whitelist ONE ip (myself) from accessing a device via ssh. How do I ban ALL ip except myself (1 ip that i am using?) Context: I saw there are 500 ip attacks yesterday, I just wanna make ...
user3222184's user avatar
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Very high load even nothing is done

I have the below Ubuntu server hosted by a commercial hoster. The hoster says he has no clue. Attached a screenshot from top where can be seen which processes are slowing down the server. It's more or ...
Peter VARGA's user avatar
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249 views

Fail2Ban vulnerability after reboot

I am very happy with fail2ban for protecting my server except for one issue. After a reboot, each banned ip address is added to iptables one at a time. On one server, I have about 7500 permanently ...
Rick's user avatar
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-1 votes
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Help to make a fail2ban filter

I've already done some filters for my fail2ban, but just simple things, like: [Definition] failregex = ^ .* "GET .*/wp-login.php ignoreregex = i don't use wordpress on my server, so i block a ...
alebal's user avatar
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Help to complete a script (fake google IPs, maybe fail2ban)

I monitored the google ip that accessed my server for a few years and identified these masks: 66.249.64.0/19 66.102.0.0/20 64.233.160.0/19 34.64.0.0/10 216.58.192.0/19 74.125.0.0/16 Then I created ...
alebal's user avatar
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How to configure fail2ban for both TCP and UDP port?

I want to ban some DNS requests coming to my named server. The server normally listens both TCP and UDP port 53 and logs the requests to /var/log/named/query.log file. So, I added the following entry ...
FedKad's user avatar
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Fail2ban - IP banned is able to connect

I am using Ubuntu Server 20.04. I installed fail2ban and it is correctly banning the IP but still its able to connect. Giving below the fail2ban.log snippet. 2021-07-19 09:52:14,543 fail2ban.filter ...
Sriram Rayadurg's user avatar
-1 votes
2 answers
675 views

fail2ban not manipulate iptables

i googled some articles like"how to install fail2ban on ubuntu 20.04", none of them mentioned my situation. my env: new ubuntu 20.04 installation on vmware player.straight install fail2ban. ...
Ivan's user avatar
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SSH timing out - no longer able to access server after installing Fail2ban

I decided to improve security on my Ubuntu 20.04 server by installing fail2ban. Looks like I went too far :/ I was previously logging in fine using SSH. I installed a default fail2ban install, copied ...
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Fail2ban is not able to connect to mysql under reboot prosess, both shutdown and startup process, Can't connect to MySQL server on '127.0.0.1' (111)

I'm running a LAMP setup on Ubuntu 18.04.5 LTS (GNU/Linux 4.15.0-135-generic x86_64). I have integrated fail2ban and db using documentation from https://docs.iredmail.org/fail2ban.sql.html#fail2ban-...
grindstr's user avatar
3 votes
0 answers
11k views

How to solve ssh error "ssh_exchange_identification: read: Connection reset by peer" on ubuntu server correctly

Related very closely to question and answers like: How to fix "ssh_exchange_identification: read: Connection reset by peer" error? My reputation is too low to comment or provide answer ...
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"top" shows fail2ban and sshd at the very top, hogging CPU usage

top shows fail2ban and sshd at the very top and hogging CPU usage. top - 19:30:57 up 1 day, 9:44, 1 user, load average: 41.03, 41.02, 41.02 Tasks: 738 total, 1 running, 737 sleeping, 0 stopped, ...
user14045797's user avatar
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Can't block specific IP address with iptables, Ubuntu 16.04

I'm trying to troubleshoot Fail2ban recognizing our http-get-dos trigger, but not actually banning the offending host. I can see it adding entries to iptables rules, but they don't have any affect. So ...
Joe Miller's user avatar
0 votes
1 answer
563 views

Fail2ban doesn't persist manual banned IPs after service restart

Just upgraded from f2b v0.9.6 to v0.10.5 on Ubuntu 14.04 using this thread, and it is banning normally according to my old jails that i copied from my previous version. But when i restart the service,...
MohammedSimba's user avatar
1 vote
0 answers
226 views

Fail2ban continuous log flood, what's happening?

A couple of days ago I noticed my server got very sluggish. When I investigated I noticed fail2ban was going crazy, the fail2ban-server process taking up 50% of CPU, and the fail2ban log file is ...
Pantalaimon's user avatar
3 votes
1 answer
3k views

How to prevent x11vnc attacks: attempts to unauthorized logins?

My computer was freezing for 1 second every 5 seconds. I found it was someone repeatedly trying to log in through x11vnc. Is there some way I can have it reject connections from an IP address for a ...
beauxq's user avatar
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17 votes
2 answers
3k views

IP getting access even after blocking

78.128.113.62 - - [04/Jan/2020:19:59:33 +0530] "GET /efk-dashboard HTTP/1.1" 404 66914 "-" "python-requests/2.13.0" There are multiple access records like this even after I have run the commands ufw ...
Joshi's user avatar
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Fail2ban not sending email

I set up Fail2ban as per this page: https://help.ubuntu.com/community/Fail2ban I tried looking in several pages among others: https://stackoverflow.com/questions/25890510/fail2ban-not-sending-email-...
brat's user avatar
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626 views

fail2ban banned IP still able to connect

Having trouble with Fail2ban: Background: Using Ubuntu Server 18.04.2 Installed ufw Installed and set up ssh with keys, random port other than 22, working Installed fail2ban Issue: On same LAN ...
brat's user avatar
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5 votes
1 answer
1k views

How should I write the fail2ban -> apache-badbots.conf rules?

I often have to add new rules to the apache-badbots.conf file, and every time I have the doubt that it no longer works... For example, this is my current apache-badbots.conf file: [Definition] ...
alebal's user avatar
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ssh, fail2ban and max login attempts

I am testing fail2ban in a Ubuntu 18.04 LTS server in VirtualBox. I set maxretry = 3 in /etc/fail2ban/jail.local, and I tried to ssh connect from another virtual machine with a wrong password. After ...
Asarluhi's user avatar
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1 vote
1 answer
2k views

Fail2ban Dynamic IP

I need help setting up my Fail2ban. I have a client that your IP is Dynamic. and every time I need to wait for it to tell me the IP so I can include ignoreip. How can i make a script to collect if ...
Fernando's user avatar
4 votes
1 answer
3k views

fail2ban actions to broaden the banned IP range

Is there a way to have fail2ban ban the entire class C network from which a ban address comes from? A
A.Adverse's user avatar
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Regex for fail2ban config file to match pregreet lines in mail.log

The lines in mail.log to match are like: May 6 10:06:16 mikes-serverbox postfix/postscreen[15486]: PREGREET 14 after 0.1 from [173.225.99.104]:57130: EHLO ylmf-pc\r\n May 9 11:36:36 mikes-...
viDim's user avatar
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Block IP:s recognized by logwatch using fail2ban+ufw?

I got fail2ban and logwatch running on my server. Each day I have a few IP:s that's been probing my server and also a few "Attempts to use known hacks", as it states in the daily mail. I would like ...
Daniel Holm's user avatar
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0 answers
273 views

fail2ban duplicate log entries

I am posing this as a question.... It seems every time I restart fail2ban it re-bans all the IP addresses and possibly creates a new log entry for every previous ban. I pipe every ban to a text file ...
User6655's user avatar
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7 votes
1 answer
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Block badbot with fail2ban via user agents in access.log

How can I create a filter to block these with fail2ban? 476 Mozilla/5.0 (compatible; BLEXBot/1.0; +http://webmeup-crawler.com/) 892 ltx71 - (http://ltx71.com/) 5367 Mozilla/5.0 (...
alebal's user avatar
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3 votes
0 answers
682 views

What do the filters included in Fail2ban?

In my /filter.d/ directory of Fail2ban there are many filters. 3proxy.conf asterisk.conf ejabberd-auth.conf lighttpd-auth.conf oracleims.conf selinux-...
alebal's user avatar
  • 463
1 vote
1 answer
92 views

Fail2ban ignoreip command crashing fail2ban

Recently I updated ubuntu 16.04 with the latest security updates and all of a sudden ignoreip stops fail2ban from running I comment this line out and it starts working Any ideas? i tried adding commas ...
Gary's user avatar
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2 votes
1 answer
6k views

Job for fail2ban.service failed because the control process exited with error

I have a basic issue on getting fail2ban started on one of my machines. I have a machine with Ubuntu 16.04 freshly installed today, and I am following a variety of instructions on fail2ban from source ...
ComputerScientist's user avatar
6 votes
1 answer
6k views

unable to install fail2ban on ubuntu 18.04

I installed ubuntu server(18.04 version) a few days ago. and I tried to install fail2ban with apt tool but couldn't do that. Here's some information on my situation. root@ubuntu:~# cat /etc/os-...
NoFence's user avatar
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1 vote
1 answer
2k views

Fail2Ban not banning

Fail2Ban works fine with the built-in jails, but my custom OpenVPN jail doesn't ban anything, neither does my NGINX-DoS jail. The output of sudo fail2ban-client status openvpn is: Status for the jail:...
user8292439's user avatar
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5 votes
2 answers
20k views

Fail2ban Error on start

Recently, I have tried restarting Fail2ban and I have received an error, making it impossible to start... The full error I received from systemctl status fail2ban is as follows: Jan 03 18:27:02 ...
NerdOfCode's user avatar
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1 vote
0 answers
955 views

can't set up fail2ban Ubuntu 16.04

I run: sudo apt-get update sudo apt-get install fail2ban sudo cp /etc/fail2ban/jail.conf /etc/fail2ban/jail.local With out activating any jails or anything else: sudo systemctl restart fail2ban ...
newcat1000's user avatar
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0 votes
1 answer
1k views

UFW is not blocking IPs

so im working with fail2ban, ufw, and wordpress (NGINX). I made plugin for creating 401 if someone fail to login function wp_login_failed_403_res() { status_header(403); } add_action( '...
NoobyAFK's user avatar
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1 vote
1 answer
124 views

fail2ban makes nc fail

I have a problem with fail2ban here. (Configs see below) Before I had it I used nc -4 -d -n -z -w 1 <SERVER IP> 22 from my PC in a script to check if the server is reachable on SSH (should ...
derHugo's user avatar
  • 3,336
3 votes
1 answer
1k views

Fail2Ban blocks my IP address due to blocked traffic, how do I stop it from banning me?

I need to know what program or what specific rule is banning my ip as it happens often when I am programming. It will ban my routers internal IP since I am connecting through the LAN. Then after ...
Riz-waan's user avatar
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1 vote
0 answers
773 views

Fail2ban Not banning IP Address

I am using this jail in /etc/fail2ban/jail.local: [nginx-bots] enabled = true port = http,https filter = nginx-bots logpath = /var/log/nginx/access.log* maxretry = 1 bantime = 172800 ...
JoaMika's user avatar
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0 answers
3k views

Protect Samba with fail2ban?

I know this isn't the smartest idea, but I use an ssh tunnel to forward samba to my raspberry pi NAS from my server. How can I protect samba against brute force attempts? I couldn't get fail2ban to ...
user8292439's user avatar
  • 3,798
2 votes
1 answer
1k views

fail2ban banned my IP but I still can SSH

Hi I am trying to use fail2ban to protect my server's SSH. I can see my ip is banned from: sudo fail2ban-client status sshd But I can still ssh in the machine through the same ip. Why the fail2ban ...
Coroner_Rex's user avatar