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Erwin_25552's avatar
Erwin_25552
Icon for Nimbostratus rankNimbostratus
May 04, 2018

Forwarding traffic to specific port

Hi All

 

Building a IRule were a specific path is directed towards a node / member with a specific port.

 

To do so I created a datagroup (string) where each path has a value (port) So far the Irule below works fine, just with one node.

 

when HTTP_REQUEST { set URI [string tolower [HTTP::uri]] log local0. "Path is $URI" if { [class match $URI starts_with ITSM_URL_Port] } { set port [class match -value [string tolower [HTTP::uri]] starts_with ITSM_URL_Port] log local0. $port node $port } else { log local0. "no match - [HTTP::uri] "} }

 

But the next challenge will be when a second server is added. I tried several methods i.e. using the LB_SELECTED event were the IP address is captured in a variable and use in the node command like for example : node $server_address $port, were the server address is fetched from the [LB::server addr] command.

 

For example :

 

when HTTP_REQUEST { set URI [string tolower [HTTP::uri]] log local0. "Path is $URI" if { [class match $URI starts_with ITSM_URL_Port] } { set port [class match -value [string tolower [HTTP::uri]] starts_with ITSM_URL_Port] log local0. $port } else { log local0. "no match - [HTTP::uri] "} }

 

when LB_SELECTED {

 

set server_address = [LB::server addr } node $server_address $port

 

}

 

In the logging we see that the self-ip is returned instead of the real server address.

 

Any idea why the self-ip is returned instead of the server address? We running version 12.1.2

 

Kind regards

 

application delivery
iRules
  • Simon_Blakely's avatar
    Simon_Blakely
    Icon for Employee rankEmployee
    May 06, 2018

    Try the following - shifting the node command to the HTTP_REQUEST event

    when HTTP_REQUEST { 
  set URI [string tolower [HTTP::uri]] 
  log local0. "Path is $URI" 
  if { [class match $URI starts_with ITSM_URL_Port] } 
  { 
    set port [class match -value [string tolower [HTTP::uri]] starts_with ITSM_URL_Port] 
    log local0. $URI selects $server_address:$port
    node $server_address $port
    } else { 
      log local0. "no match - [HTTP::uri] "
    } 
  }
  when LB_SELECTED {
    set server_address = [LB::server addr]
  }