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MartinM_58357's avatar
MartinM_58357
Icon for Nimbostratus rankNimbostratus
May 29, 2014

HTTP::uri caching

Hi

Irule snippet...


set foo [HTTP::uri]


log local0.info "foo = $foo"
set foo [string map -nocase {"jim" "fred"} [HTTP::uri]]
log local0.info "foo =  $foo"
set HTTP::uri foo


log local0.info "HTTP::URI =  [HTTP::uri]"

...gives...


May 29 09:23:49 10.39.49.55 tmm tmm[4854]: Rule XXXX :  foo = /jim/services/ServiceA


May 29 09:23:49 10.39.49.55 tmm tmm[4854]: Rule XXXX :  foo =  /fred/services/ServiceA


May 29 09:23:49 10.39.49.55 tmm tmm[4854]: Rule XXXX :  HTTP::URI =  /jim/services/ServiceA

...and the URI passed onto the pool is /jim/services/ServiceA, when I want it to be /fred/services/ServiceA - web logs of the server in the pool show that /fred/services/ServiceA is being passed to the server

Why isn't the HTTP::uri assignment actually happening/sticking? Looks like there's some caching going on in the iRule?

It's the only iRule associated with the VS

Grateful for any assistance - this is causing a big problem at the moment

Thanks Martin

application delivery
devops
iRules
LTM

10 Replies

  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    May 29, 2014

    e.g.

     config

[root@ve11a:Active:In Sync] config  tmsh list ltm rule qux
ltm rule qux {
    when HTTP_REQUEST {
  log local0. "\[HTTP::uri\] = [HTTP::uri]"
  set newuri [string map -nocase {"jim" "fred"} [HTTP::uri]]
  HTTP::uri $newuri
  log local0. "\[HTTP::uri\] = [HTTP::uri]"
}
}

 /var/log/ltm

[root@ve11a:Active:In Sync] config  tail -f /var/log/ltm
May 29 01:43:00 ve11a info tmm1[9801]: Rule /Common/qux : [HTTP::uri] = /jim/services/ServiceA
May 29 01:43:00 ve11a info tmm1[9801]: Rule /Common/qux : [HTTP::uri] = /fred/services/ServiceA
  • MartinM_58357's avatar
    MartinM_58357
    Icon for Nimbostratus rankNimbostratus
    May 29, 2014

    Thanks for the prompt reply

     

    I added a $ into

     

    set HTTP::uri foo

     

    i.e. set HTTP::uri $foo

     

    ..but still the same result :(

     

    "BIG-IP 10.2.3 Build 112.0 Final" if that makes a difference?

     

    I've read: https://devcentral.f5.com/questions/need-workaround-for-10x-caching-issue-with-httpuri-updates ..which seems to be a similar issue, resolved by changing iRule order - but I only have this one irule.

     

    Any ideas please...

     

    Thanks Martin

     

  • nitass_89166's avatar
    nitass_89166
    Icon for Noctilucent rankNoctilucent
    May 29, 2014

    e.g.

     config

[root@ve10:Active] config  tmsh list ltm rule qux
ltm rule qux {
    when HTTP_REQUEST priority 100 {
  log local0. "\[HTTP::uri\] = [HTTP::uri]"
  set newuri [string map -nocase {"jim" "fred"} [HTTP::uri]]
  HTTP::uri $newuri
}
when HTTP_REQUEST priority 200 {
  log local0. "\[HTTP::uri\] = [HTTP::uri]"
}
}

 /var/log/ltm

[root@ve10:Active] config  tail -f /var/log/ltm
May 29 16:44:49 local/tmm info tmm[4955]: Rule qux : [HTTP::uri] = /jim/services/ServiceA
May 29 16:44:49 local/tmm info tmm[4955]: Rule qux : [HTTP::uri] = /fred/services/ServiceA
    • nitass_89166's avatar
      nitass_89166
      Icon for Noctilucent rankNoctilucent
      May 29, 2014
      this is due to ID224251 (iRule command caching does not properly get cleared when data changes) which is fixed in 11.0.0.
  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    May 29, 2014

    e.g.

     config

[root@ve10:Active] config  tmsh list ltm rule qux
ltm rule qux {
    when HTTP_REQUEST priority 100 {
  log local0. "\[HTTP::uri\] = [HTTP::uri]"
  set newuri [string map -nocase {"jim" "fred"} [HTTP::uri]]
  HTTP::uri $newuri
}
when HTTP_REQUEST priority 200 {
  log local0. "\[HTTP::uri\] = [HTTP::uri]"
}
}

 /var/log/ltm

[root@ve10:Active] config  tail -f /var/log/ltm
May 29 16:44:49 local/tmm info tmm[4955]: Rule qux : [HTTP::uri] = /jim/services/ServiceA
May 29 16:44:49 local/tmm info tmm[4955]: Rule qux : [HTTP::uri] = /fred/services/ServiceA
    • nitass's avatar
      nitass
      Icon for Employee rankEmployee
      May 29, 2014
      this is due to ID224251 (iRule command caching does not properly get cleared when data changes) which is fixed in 11.0.0.
  • MartinM_58357's avatar
    MartinM_58357
    Icon for Nimbostratus rankNimbostratus
    May 29, 2014

    Unfortunately 11.0.0 is not an option at the moment.

     

    But it looks like splitting the "When HTTP_REQUEST" into two different priority parts has solved the problem. Well, it looks like it has - if it continues to be a problem, I'll be back

     

    Many thanks for the quick responses

     

    Martin

     

    • nitass's avatar
      nitass
      Icon for Employee rankEmployee
      May 29, 2014
      just want to be clear. this is about caching data when logging only. uri is changed correctly.