Linux System Admins Blog

The ASA 5505 is the smallest (and cheapest) solution from the current Cisco hardware security appliances. Still, if we have the proper software license (like Security Plus for example) we can use the ASA5505 to setup rather complex solutions. This post will show how we can setup a pair of ASA5505 in failover configuration, solution [...]

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If you run a version of Java JRE newer than v6 Update 10 (latest at this time is V6 Update 12) and see this error when trying to connect to a Cisco ASA ASDM interface:
“ASDM is unable to continue loading. Click OK to exit from ASDM.
Unconnected sockets not implemented.”
then you are probably running an older [...]

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This post will show how you can easily upgrade ASDM (Cisco Adaptive Security Device Manager for ASA) to the latest version on a Cisco ASA5500 firewall using the command line interface. In order to do this you will need the latest asdm image (you will need a proper cisco cco user and contract to download [...]

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The Domain Name System (DNS) is responsible for translating host names to IP addresses (and vice versa) and is critical for the normal operation of internet-connected systems. DNS cache poisoning (sometimes referred to as cache pollution) is an attack technique that allows an attacker to introduce forged DNS information into the cache of a caching [...]

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One of our longer running projects for while now has been to become PCI DSS compliant. For those of you that have never heard of it, PCI stands for Payment Card Industry and DSS stands for Data Security Standards. Basically what it comes down to is that the credit card companies have gotten together and [...]

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