Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

SASL LOGIN authentication failed: authentication failure

Posted on 2016-08-11
1
Medium Priority
?
153 Views
Last Modified: 2016-08-12
Hi

I am running CentOS and several times see "SASL LOGIN authentication failed: authentication failure". Seems someone is trying to logon to my mail server illegally.

I have installed fail2ban to block such cases automatically. But I want to test that by simulating this situation. I created an account in my thunderbird mail client and provided wrong credentials to my server but this doesn't generate anything in my server's maillog.

Can someone please suggest me how can I produce "SASL LOGIN authentication failed: authentication failure" ?
0
Comment
Question by:sysautomation
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
1 Comment
 
LVL 25

Accepted Solution

by:
Tomas Helgi Johannsson earned 2000 total points
ID: 41751930
Hi!

You will need to look into the conf files for fail2ban to seem what IP addresses are ignored (localhost is by default ignored).
Make sure that your LAN IP address range is not ignored (except one IP address that you can use to safely log into your server) and then test  (using a simple telnet command http://www.anta.net/misc/telnet-troubleshooting/smtp.shtml ) from your LAN (other than your safe IP).
https://www.digitalocean.com/community/tutorials/how-to-protect-ssh-with-fail2ban-on-centos-7
Just make sure you don't lock yourself out completely. ;)

Regards,
     Tomas Helgi
0

Featured Post

TCP/IP Network Protocol Cheat Sheet

TCP/IP is a set of network protocols which is best known for connecting the machines that make up the Internet. The truth is that TCP/IP is one of the oldest network protocols and its survival is mainly based on its simplicity and universality.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Utilizing an array to gracefully append to a list of EmailAddresses
Want to know how to use Exchange Server Eseutil command? Go through this article as it gives you the know-how.
The video tutorial explains the basics of the Exchange server Database Availability groups. The components of this video include: 1. Automatic Failover 2. Failover Clustering 3. Active Manager
Connecting to an Amazon Linux EC2 Instance from Windows Using PuTTY.
Suggested Courses

704 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question