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Introduction RAM Cache is a feature that provides the ability to serve content to your clients directly from the memory of your F5 appliance. This benefits both client and server by reducing response latency and also server load. What is Cached ? Heres a summary, The following items are cached, All 200, 203, 206, 300, … Read more
The F5 offers a number of different ways to you can represent your data via iRules such as variables, tables, datagroups and arrays. Within this article we will look at the variables. There are 2 main types of variables, local and global. Local Local variables represent data within your local namespace, and are assigned the … Read more
The Vary Header The vary header is sent within the servers response to the client and instructs any intermediary caches to cache a separate instance based on the headers specified within the vary header. Encoding Headers As our example is based around the following HTTP headers, here is a quick summary of each, Content-Encoding (HTTP … Read more
Issue You may observe the ASA incorrectly proxy ARPing for an IP address resulting in connectivity issues . Background Within 8.4(2) and 8.6(1) the following NAT changes were introduced.This basically states that Proxy ARP is enabled by default on both static and identity based NAT statements. Reference : http://www.cisco.com/en/US/docs/security/asa/asa84/configuration/guide/intro_intro.html Identity NAT configurable proxy ARP and … Read more
Recently I found myself in a situation where I needed to recompile mod_wgsi against a newer version of Python. This involves recompiling Python with the correct flags, then recompiling mod_wsgi using the newly compiled Python. Below shows the steps, Check Version First of all check what version of Python mod_wsgi was compiled with. [root@server]# ldd … Read more
TACACS+ accounting was first supported within BIG-IP version 10.2.0. Within this article we will show your the commands required to enable this feature. Configure First of all you will need to enable accounting within your authentication settings (this can be found within the GUI under ‘System / Users / Authentication’) modify sys db config.auditing.forward.destination value … Read more
By: Ayman Hammoudeh Introduction Pivoting refers to method used by penetration testers that uses compromised systems to attack other systems on the same network to avoid restrictions such as firewall configurations, which may prohibit direct access to all machines. For example, an attacker compromises a web server on a corporate network; the attacker can then … Read more
Issue When using scp to copy a file the file fails to transfer, however there is no error message. Solution This issue can occur due echo commands within your .bashrc and how the scp program handles the output from these commands. This is a known bug within scp which can be viewed here. To resolve this … Read more
Issue When viewing the UIE persistence records you observe that the Client Addr field is not populated. root@f5ltm(Active)(tmos)# show ltm persistence persist-records all-properties Sys::Persistent Connections universal – 172.16.100.200:80 – 192.168.1.31:80 ———————————————————– TMM 0 Mode universal Key 8ffa6c0012825a76b3b68d10a9c68ad3 Age (sec.) 4 Virtual Name VS-172.16.100.200-80 Virtual Addr 172.16.100.200:80 Node Addr 192.168.1.31:80 Pool Name POOL-172.16.100.200-80 Client Addr :: … Read more