Forum Discussion
NimbostratusNeed assistance on below for transferring ACE to F5 LTM 11.5.1
Hi
Please suggest what I can do on the F5 LTM for the below config on ACE.
parameter-map type http pre-idp_http_PM set header-maxparse-length 8196 set content-maxparse-length 8196 length-exceed continue
sticky http-cookie pre-idp pre-idp cookie insert browser-expire serverfarm pre-idp sticky http-cookie pre-idp pre-sp cookie insert browser-expire serverfarm pre-sp sticky http-cookie pre-holvi pre-holvi cookie insert browser-expire serverfarm pre-holvi
The behavior of above config is as follows
- header-maxparse-length 8196 bytes (max number of bytes to check for a cookie, HTTP header or URL)
- content-maxparse-length 8196 bytes (max number of bytes to check for a content string)
- If cookies, HTTP headers, and URLs exceed the maximum parse length continue load balancing."
11 Replies
yogesh_gaikwad_Below is the behavior of each command parameter-map type http pre-idp_http_PM -------------- Configure advanced HTTP behavior for SLB connections set header-maxparse-length 8196--------------- Max number of bytes that the ACE parses to check for a cookie, HTTP header, or URL (default 4096) set content-maxparse-length 8196 --------------- Max number of bytes that the ACE parses to check for a content string (default 4096) length-exceed continue --------------- "If cookies, HTTP headers, and URLs exceed the maximum parse length continue load balancing. The connection is not dropped but rather load balanced to a less specific match, like class-default if configured. After that, all the subsequent GET requests are not parsed anymore."
Brad_ParkerCirrus
Well, do you really want to limit the LTM to 8k for the headers? Default http profile in LTM accepts 32k so you don't have to worry about that(LTM is superior to ACE, we are almost done replacing all of our ACEs). For the "sticky http-cookie..." you will want to use a cookie persistence profile with the default session cookie option to match the config. Here's a little more info on cookie persistence, https://support.f5.com/kb/en-us/solutions/public/6000/900/sol6917.html.
- yogesh_gaikwad_Hi Brad, Thanks for your reply I am transferring the services as is to avoid any problems, I am not sure if the customer had requested such kind of config on the ACE, I will try not to limit the LTM to 8k for the headers, but if in case it does not work as expected, then what should be the procedure to achieve similar config on F5 as the above one BR, Yogesh
- Brad_ParkerWith how the ACE is working I don't anticipate you having to change this as ACE just allows it through after reading 8k, its non-blocking. However, on LTM if you choose to change the "Maximum Header Size" any request with a header larger than that will have its connection reset.
- yogesh_gaikwad_So there is no option on the F5 to continue the load balancing even if the header size increases of a specific request?
- Brad_Parker_139
Nacreous
Well, do you really want to limit the LTM to 8k for the headers? Default http profile in LTM accepts 32k so you don't have to worry about that(LTM is superior to ACE, we are almost done replacing all of our ACEs). For the "sticky http-cookie..." you will want to use a cookie persistence profile with the default session cookie option to match the config. Here's a little more info on cookie persistence, https://support.f5.com/kb/en-us/solutions/public/6000/900/sol6917.html.
- yogesh_gaikwad_Hi Brad, Thanks for your reply I am transferring the services as is to avoid any problems, I am not sure if the customer had requested such kind of config on the ACE, I will try not to limit the LTM to 8k for the headers, but if in case it does not work as expected, then what should be the procedure to achieve similar config on F5 as the above one BR, Yogesh
- Brad_Parker_139With how the ACE is working I don't anticipate you having to change this as ACE just allows it through after reading 8k, its non-blocking. However, on LTM if you choose to change the "Maximum Header Size" any request with a header larger than that will have its connection reset.
- yogesh_gaikwad_So there is no option on the F5 to continue the load balancing even if the header size increases of a specific request?
