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sandiksk_35282's avatar
sandiksk_35282
Icon for Altostratus rankAltostratus
Oct 17, 2016

Irule not working as expected

I created an irule when CLIENT_ACCEPTED { set default_pool [LB::server pool] }   when HTTP_REQUEST { switch -glob [string tolower [HTTP::uri]] { "/customerdetails" - "/webo...
application delivery
iRules
LTM
  • VernonWells's avatar
    VernonWells
    Oct 19, 2016

    No need for any string command. If you don't want to normalize the case, then:

     

    when HTTP_REQUEST {
    switch -glob [HTTP::uri] {
        ... etc ... 
    }
}

     

    However, again, you probably want to use HTTP::path, since that's what you're actually matching on. For the case your provide, it would be something like this:

     

    when HTTP_REQUEST {
    switch -glob [HTTP::path] {
        "*/MembershipEdit" {
            pool poolB
        }
    }
}

     

    For the example URL you provided, what you're trying to match is essentially "if the Target-Request path ends_with /MembershipEdit, then use poolB". With glob matching:

     

        switch [HTTP::path] {
        "/foo" {...}    ; means match if path is exactly /foo
        "*/foo" {...}   ; means match if path ends with /foo
        "/foo/*" {...}  ; means match if path starts with /foo/
        "*/foo/*" {...} ; means match if path contains /foo/
    }

     

    For what it's worth, I suspect that what you really mean is:

     

    when HTTP_REQUEST {
    switch -glob [HTTP::path] {
        "*/CustomerDetails" -
        "*/WebofferList" -
        "*/MembershipEdit" {
            pool poolB
        }
    }
}

     

    What I mean is, I suspect in all cases you are trying to match something at the end of the path, and since you are not normalizing the case (and generally, not normalizing the case of the path is the correct choice), then you must make sure the case matches.

lmiestc_26212's avatar
lmiestc_26212
Icon for Cirrus rankCirrus
Oct 17, 2016

Read this one https://devcentral.f5.com/articles/switch-gone-wild-using-wildcards-with-the-tcl-quotswitchquot-command especially the An example of the "contains" functionality where it selects a pool depending on of the URI and then if no prior match go to the default pool.

So if looking at your irule

when HTTP_REQUEST {
  switch -glob [string tolower [HTTP::uri]] {
    "/customerdetails" -
    "/webofferlist" - 
    "membershipedit/" {
      If URI contains any of the above pool poolB 
    }
    default {
      No prior match so take some default action
      pool name_of_your_default_pool
    }
  }
  Uncomment below if you want to log and see which URI goes to what pool for troubleshooting 
  log local0. "URI: [HTTP::uri] Pool: [LB::server pool]"
}