IT Security & Network Engineering Knowledge Base

Practical documentation and technical guides on network security, firewalls, Linux systems, monitoring, and automation.
We feature technical articles across the entire IT spectrum - Built from real-world experience and continuously updated.

ASA L2L VPN is not Passing Traffic when VPN Filter is Applied

Within the Cisco Adaptive Security Appliance Software Version 8.2(2) you may find that when you have a group-policy (vpn filter) applied to your tunnel group that some traffic is not being allowed through the VPN. This is a bug with 8.2(2), to resolve the issue you will need add the destination ports to the group-policies … Read more

Endpoint Connect Installation / Troubleshooting Guide

What is EndPoint Connect ? Check Point`s Endpoint Connect software provides a number of client side security based features such as Anti-virus/Anti-spyware. Firewall/Email Protection, Program Control and Remote Access VPN. This document will only details and discuss the Remote Access VPN section of the Endpoint Connect Software. Note : This document will refer to the … Read more

Check Point Web Visualization Only Provides Part of Policy

When using the Check Point Web Visualization tool and trying to obtain the policy for a Cluster object you may receive one of the following errors/issues : The policy is saved as an .html file but it is only showing part of the policy. You receive one of the following errors when running the Web … Read more

Running a packet capture on a SourceFire Sensor

Below shows you the required steps for running a packet capture on a SourceFire Sensor. Which Interfaces are Sniffing ? First of all we get a list of interfaces that is are sniffing for malicious traffic. Note : the fps normally relate to eth. Though you still use the fps reference within the tcpdump. ps … Read more

IE6 with Passive FTP: File download fails via Netscreen

You may find when trying to download a file from your FTP server using Internet Explorer 6 with “Folder View Enabled” when using Passive FTP the file download transfer will fail after a short time period. This can be down to Internet Explorer sending TCP packets with sequence numbers which are outside that of the … Read more

I am unable to clear the VPN SA`s using the vpn tu command

If you are unable to clear the VPN SA`s using the “vpn tu” command you may want to try using the following commands vpn shell /show/tunnels/ike/peer/[remote gw ip] vpn shell /show/tunnels/ipsec/peer/[remote gw ip] vpn shell /tunnels/delete/IKE/peer/[remote gw ip] vpn shell /tunnels/delete/IPsec/peer/[remote gw ip] The reason to this can be down to a number of issues … Read more

ClusterXL Active Attention / Interface Active Check Error

This article will provide the required troubleshooting steps for resolving the issue of the “Interface Active Check” error within ClusterXL. First of all you spot there is an error within ClusterXL using the following command, root@firewall # cphaprob stat Cluster Mode:   Legacy High Availability (Active Up) Number     Unique Address  Assigned Load   State 1          192.168.12.1   100%            … Read more

Upgrade SMS Brightmail Appliance from 7.6.1-14 to 8.0.0.24

This document will provide the required steps in order to upgrade the SMS Brightmail appliance from 7.6.1-14 to 8.0.0.24. Backup 1.      Navigate to “Administration > Hosts > Version” 2.      Click “Backup Now” 3.      Under “Backup Data” select “Full Backup” 4.      Under “Backup To” select “Store Backup on server” 5.      Click “Backup Now” 6.      Download the … Read more