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JohnL_247646's avatar
JohnL_247646
Icon for Nimbostratus rankNimbostratus
Feb 03, 2016

Need help with Cisco ACE header rewrite to irule

I need some help doing this conversion from Cisco Ace to iRule. There is a header request that convert the users URL request from "hostA.companyA.com/whatever/comes/after" replace "host1.companyA.com:64592/whatever/comes/after" and a header response that converts it back so the user will only see hostA.companyA.com/whatever/comes/after. We need to make the rewrite transparent to the user and the '/whatever/comes/after' will need to stay the same.

 

There is the ACE code..

 

action-list type modify http login header rewrite request Host header-value "hosta[.]companyA[.]com(.)" replace "host1.companyA.com:64592%1" header rewrite response Location header-value "https://host1.companyA.com:64592/(.)" replace "https://hosta.companyA.com/%1"

 

Thanks

 

devops
iRules

4 Replies

  • Kai_Wilke's avatar
    Kai_Wilke
    Icon for MVP rankMVP
    Feb 03, 2016

    Hi John,

    an ACE action-list of...

    action-list type modify 
    http login 
            header rewrite request Host header-value "hosta[.]companyA[.]com(.)" replace "host1.companyA.com:64592%1" 
            header rewrite response Location header-value "https://host1.companyA.com:64592/(.)" replace "https://hosta.companyA.com/%1"

    ... could be translated to ...

    when HTTP_REQUEST {
    if { [string tolower [HTTP::host]] equals "hosta.companya.com" } then {
        HTTP::header replace Host "host1.companyA.com:64592"
    }
}
when HTTP_RESPONSE {
    if { [string tolower [HTTP::header value Location]] starts_with "https://host1.companya.com:64592" } then {
        HTTP::header replace Location "https://hosta.companyA.com[getfield [HTTP::header value Location] ":64592" 2]"
    }
}

    Note: I'm using 

    [string tolower]
    to make it more robust. So keep an eyee on lower CASE formating for the equals and starts_with comparsions.

    Cheers, Kai

    • Kai_Wilke's avatar
      Kai_Wilke
      Icon for MVP rankMVP
      Feb 05, 2016
      Getfield splits the given input on every ":64592" and then uses the 2nd block...
  • JohnL_247646's avatar
    JohnL_247646
    Icon for Nimbostratus rankNimbostratus
    Feb 05, 2016
    I modified that a bit in my testing enviroment when HTTP_REQUEST { if { [string tolower [HTTP::host]] equals "lb.abc.com" } then { HTTP::header replace Host "10.10.192.111" } } when HTTP_RESPONSE { if { [string tolower [HTTP::header value Location]] starts_with "http://" } then { HTTP::header replace Location "https://lb.abc.com[getfield [HTTP::header value Location] ":80" 2]" } } Not working and keep getting this in the ltm log. error: [undefined procedure: HTTP::Location][HTTP::Location]