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dkinsler_23191's avatar
dkinsler_23191
Icon for Nimbostratus rankNimbostratus
Jan 26, 2010

Most efficient way to write this

My devs are asking me to Do many many redirects based on various mispellings our our URL's. I am worried about the extra processing of every request going through these lists of if/then statements. Is there a more processor/network friendly way to write this? Keep in mind im actually talking about adding like 30 of these, this is a small sampling. I dont want to over tax the LB or slow down my responses. Any help would be greatly appriciated.

 

 

when HTTP_REQUEST {

 

if { [HTTP::host] equals "connection1.net"} {

 

HTTP::redirect "http://www.connection1.com[HTTP::uri]"

 

}

 

if { [HTTP::host] equals "connection1.org"} {

 

HTTP::redirect "http://www.connection1.com[HTTP::uri]"

 

}

 

if { [HTTP::host] equals "connection1.biz"} {

 

HTTP::redirect "http://www.connection1.com[HTTP::uri]"

 

}

 

if { [HTTP::host] equals "connection2.com"} {

 

HTTP::redirect "http://www.connection1.com[HTTP::uri]"

 

}

 

if { ([HTTP::host] equals "www.connection1.org") and ([HTTP::uri] equals "/")} {

 

HTTP::redirect "http://www.connections1.com/folder1/home.aspx"

 

}

 

if { ([HTTP::host] equals "www.connection1.net") and ([HTTP::uri] equals "/")} {

 

HTTP::redirect "http://www.connection1.com/folder1/home.aspx"

 

}

 

if { ([HTTP::host] equals "www.connection1.biz") and ([HTTP::uri] equals "/")} {

 

HTTP::redirect "http://www.connection1.com/folder1/home.aspx"

 

}

 

if { ([HTTP::host] equals "www.connection1.com") and ([HTTP::uri] equals "/")} {

 

HTTP::redirect "http://www.connection1.com/folder1/home.aspx"

 

}

 

}
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  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jan 26, 2010
    The most efficient option might be to get a new IP address to resolve all the alternate spellings to and then use however complicated an iRule that you want.

    Else, if you need to stick with one address, you can put the real hostname first in a switch statement and the rest afterward. That way you would only do one evaluation of the host header value for the majority of requests. I don't think evaluating the host header several times in a switch statement would add that much overhead anyhow, but it's always good to try to make things as efficient as possible. 

     
 when HTTP_REQUEST { 
  
     Check the requested host header (set to lowercase) 
    switch [string tolower [HTTP::host]] { 
       "realdomain.example.com" { 
           do nothing 
       } 
       "alternatespelling1.example.com" { 
           check the URI and/or redirect request 
       } 
       "alternatespelling2.example.com" { 
           check the URI and/or redirect request 
       } 
       default { 
           no match, take some default action? 
       } 
    } 
 }

    Aaron
  • The_Bhattman's avatar
    The_Bhattman
    Icon for Nimbostratus rankNimbostratus
    Jan 26, 2010
    Hi dkinslerUser,

    I suppose you could use the switch command with IF statements

    Here is untested example 

     
  
 when HTTP_REQUEST { 
   switch -glob [string tolower[HTTP::host]] { 
    "connection1.net" - 
    "connecton1.org" - 
    "connection1.biz" - 
    "connection2.com" - { HTTP::redirect "http://www.connection1.com[HTTP::uri] } 
    default { 
      if [HTTP::uri] eq "/" } { 
       switch -glob [string tolower[HTTP::host]] { 
        "www.connection1.org" - 
        "www.connection1.net" - 
        "www.connection1.biz" - 
        "www.connection1.com"  { HTTP::redirect "http://www.connection1.com/folder1/home.aspx" } 
       } 
      } 
     } 
   } 
 }

    Bhattman