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Forum Discussion

Patti_G_72768's avatar
Patti_G_72768
Icon for Nimbostratus rankNimbostratus
Oct 21, 2013

iRule for missing or blank headers (user-agent and accept)

Hi all, I'm working on another iRule creation. I need to create a rule that will detect if the request headers for user-agent and/or accept is blank/missing. I also need to be able to exclude uri ext...
application delivery
devops
iRules
What_Lies_Bene1's avatar
What_Lies_Bene1
Icon for Cirrostratus rankCirrostratus
Oct 21, 2013

It's slightly less specific but this should work (note the HTTP::header command will return null if the header doesn't exist or if the header's value is null);

if { [HTTP::uri] ends_with "rss" or [HTTP::uri] ends_with "smil" } {
 log local0. "URI extension is rss or smil." 
 Optionally drop the traffic
 reject 
 Stop executing the irule
 return }

elseif { [HTTP::header "User-Agent"] eq "" } {
 log local0. "User-Agent header is missing or blank." }

elseif { [HTTP::header "Accept"] eq "" } {
 log local0. "Accept header is missing or blank." }