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Karthick1
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Sep 04, 2024

F5 APM Variable Assign agent

Hi All, 

i am unable to understand the usage of Variable assign agent on F5 APM. 

is there any simple way to understand 

  • In simple terms, session variables are the mechanism that APM uses to store data about user's sessions. This data has these properties:

    1- It's stored in BIG-IP's high speed session database, which is the same one that is used to store information about sticky load balancing.

    2- The data is string values that may include unicode characters. Array values are strings that are delimited by pipe | characters.

    3- The names of the variables are loosely hierarchical, but do not follow any strict naming rules. You may set a session variable with any name you like. Here's a reference with some of the common variables used.

    4- Session variables are scoped per user. User sessions do not have access to each other's session variables.

    5- Session variables (usually tokens or passwords) may be encrypted in-memory so that a process dump will not contain sensitive data. The encryption key is a combination of a dynamic nonce used for that session and the BIG-IP's master key.

     

    The Variable Assign agent simply allows you to set one of these session variables to a custom value you choose.

    Here's a lab that talks about that VPE agent, how to use it, and why it's there:

    https://f5-agility-labs-iam.readthedocs.io/en/latest/class8/module4/module4.html#