If you were running OpenVPN 2.x on Debian 10 successfully and it suddently broke with the following error after upgrading to Debian 11 : Oct 21 11:34:12 ovpnserver openvpnas[32211]: Traceback (most recent call last): Oct 21 11:34:12 ovpnserver openvpnas[32211]: File “<string>”, line 1, in <module> Oct 21 11:34:12 ovpnserver openvpnas[32211]: File “<frozen zipimport>”, line 241,… Read More »
If you are receiving a lot of cPanel notification message stating that the Exim mail server service is flapping (going down and up repeatedly) as followed : The service “exim-26,465,587” appears to be down. The service “exim-26,465,587” is now operational. You are most likely victim of some sort of denial of service attack against your… Read More »
Windows Firewall can be configured from the GUI (by using firewall.cpl UI console) and also using the command line. This quick tutorial will cover how to manipulate the rules from CLI to open, block a port and delete a rule. In a nutshell, here is the command sample: netsh advfirewall firewall add rule name=”<DESCRIPTION>” dir=in… Read More »
You may have noticed that the OSSEC Web Interface stopped working (as of today on a new installation) or after updating PHP on your server. Looking at the logs, you most likely found a similar entry: PHP Fatal error: Uncaught Error: Call to undefined function split() in /var/www/html/ossec/lib/os_lib_agent.php:111\nStack trace:\n#0 /var/www/html/ossec/site/main.php(33): os_getagents(Array)\n#1 /var/www/html/ossec/index.php(126): include(‘/var/www/html/o…’)\n#2 {main}\n thrown… Read More »
The following error message may happen from time to time when attempting to load new software version in Palo Alto Firewall or Panorama : Successfully downloaded Preloading into software manager Error: Image File Authentication Error Failed to load into software manager. Please retry. Post processing failed. Please retry PanOS always do software image integrity check… Read More »
This symptom occurred all of a sudden with Nmap 7.80 and Windows 10 version 1909 (OS build 18363.836), where nmap tries to query using interface “eth0” : Starting Nmap 7.80 ( https://nmap.org ) at 2020-06-30 11:28 Eastern Daylight Time dnet: Failed to open device eth0 QUITTING! It seems that latest Windows updates is involved in… Read More »
OpenVPN enforce by default a 15 minutes lockout policy for unsuccessful login attempts. As an avid system administrator and used to end-user struggles, you most likely encountered many times situations where a user tried to log in 20 times and blaming you that it isn’t working (all that because they are entering the wrong password,… Read More »
By default, OpenVPN has 15 minutes timeout lockout policy for consecutive unsuccessful authentication attempt (whatever you are using Local, PAM or LDAP authentication). If you want to change it to shorter or longer time period, follow these easy steps below : 1. Push the new timeout value to the configuration using this command (this example… Read More »
If you’ve noticed the following error message while starting CSF Firewall, it means that you are missing Perl modules on your system in order to fully take advantage of the capabilities of CSF. *WARNING* URLGET set to use LWP but perl module is not installed, reverting to HTTP::Tiny In order to install the missing Perl… Read More »
A friend of mine who was used to the legacy and EOL SSG/ScreenOS platform and he just jumped into the new world of SRX/JunOS gave me the motivation to write this article. As the syntax is quite different between the two platform, it may be harder to get at first and the following example should… Read More »