Check for String in TCP Payload from a specific position

I guess you may use

$[subst $varName]

Why don't you use the table command instead. You can use the virtual name

[virtual name]

 

You can even set a lifetime

 

Have a look at:

https://clouddocs.f5.com/api/irules/table.html

 

The table thing works. I guess I'll go this path. Was trying to see if I can get to work with a variable thinking the lookup would be faster than the table, but couldn't figure out how to get it to work.

Thanks!

I guess using the table command is the way to go, but if anyone can tell me why my variable thing originally didn't work (and how to make it work), it would be good for my academic interest in the topic. :)

Thanks!

look at this article about Some iRule commands temporarily suspend iRule processing

if you change the value every multiple times an hour, table may be a good solution. if this value is changed less than once an hour, the static value is still the best solution.

you can use array to store this variable

when HTTP_REQUEST {
    if { [HTTP::uri] starts_with "/changeVariable" } {
        set VIPName [string tolower [URI::query [HTTP::uri] VIPName]]
        set static::myVar(/Common/${VIPName}) foo
        log local0. "Variable name = static::myVar(/Common/${VIPName})"
        log local0. "value = $static::myVar(/Common/${VIPName})"
    }
}