Forum Discussion

NiHo_202842's avatar
NiHo_202842
Icon for Cirrostratus rankCirrostratus
Sep 16, 2016

What to do after HTTP::respond ?

Hello, I currently have a maintenance-unavailable iRule that returns a HTML page when the vs is in maintenance mode (value in datagroup list) or is not available. (LB_FAILED) My first check is if...
devops
http
irule
LTM
quit
respond
stop
Hannes_Rapp's avatar
Hannes_Rapp
Icon for Nimbostratus rankNimbostratus

Connection Close header instructs customer's browser to close the old TCP connection. It's much more kosher than just bluntly doing TCP::close which will only tear down the connection in BigIP, but not in customer's browser. Also note that you will never need to use TCP::close and Connection Close in the same conditional routine. The return function has no functional value in your use-cases, but it does no harm to keep it for readability (some admins might prefer). The event disable all function can be safely replaced by just event disable.

I've adjusted one of your conditional routines. That's how you can provide the same functions while using less lines of code.

 

if { [HTTP::uri] eq "/bip-company-logo.gif" }{
    HTTP::respond 200 content [ifile get "company-logo"] noserver Content-Type image/gif Connection Close
    event disable
}

 

Hannes_Rapp's avatar
Hannes_Rapp
Icon for Nimbostratus rankNimbostratus
Sep 16, 2016

As a general rule, a LTM Local Traffic Policy should be preferred over iRule for performance reasons (see Kai's post here: https://devcentral.f5.com/questions/advantages-of-local-traffic-policies-vs-irules). In case of maintenance iRules/Policies, instead of serving all the static content from BigIP, I'd recommend issuing a 302 temp redirect to a specialized splash/maintenance service that is managed by the application owners, not middleware admins.