Low-CPU way to insert CorrelationID

Hello rogerwow

Depending on your application, you could use cookie persistence to generate a random number for each query, which is less cost intensive.

REF - https://support.f5.com/csp/article/K83419154

Other option is to implement an iRule. Below is one idea.

when HTTP_REQUEST {
    if { !([HTTP::header exists "X-Correlation-ID"])} { HTTP::header insert "X-Correlation-ID" [string range [AES::key 256] 8 end] }
}

Other interesting topics to generate unique identifiers.

REF - https://devcentral.f5.com/questions/how-to-generate-visitor-id-uuid

REF - https://devcentral.f5.com/questions/How-random-is-rand-790690

To evaluate the cpu cost you should try it first in pre-production.

 show ltm rule IRULE_NAME

KR, Dario.