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Vivek_Datta_263's avatar
Vivek_Datta_263
Icon for Nimbostratus rankNimbostratus
Nov 27, 2017

iRule not getting executed for a URI apparently due to it's 6000+ char length

Hi all,   We have an iRule which directs a request to certain Pools depending on a regex match. However, we are observing that one particular URI doesn't follow this iRule and goes to random Pools...
application delivery
iRules
LTM
Kai_Wilke's avatar
Kai_Wilke
Icon for MVP rankMVP
Nov 27, 2017

Hi Vivek,

 

LTM and iRule are fine to handle URI's till the maximum HTTP-request size limit has been reached (default is 32768 bytes for the entire request). But APM's HUD filter and probably other TMOS modules too, are not able to handle such large URIs and may complain when URIs with >4095 chars are getting requested.

 

Although the Hyper Text Transfer Protocol specs (RFC2616) are not specifying any min/max requirement for the URL length. Some browsers are having a build-in restriction and failing to send request URIs longer than 2000 chars. So better not use those long URIs if you can't control which browser is used to access your application (aka. public website).

 

For further reading how the internet community handles this topic..

 

https://stackoverflow.com/questions/417142/what-is-the-maximum-length-of-a-url-in-different-browsers

 

Cheers, Kai