Forum Discussion

Leslie_South_55's avatar
Leslie_South_55
Icon for Nimbostratus rankNimbostratus
Oct 17, 2008

Using LB_FAILED and change the URI w/o 302

I am trying to use the 'when LB_FAILED' to send requests a pool just for apologies. The issue is that the requests coming into the VS have crazy long URI strings like '/ABC/def/g/hij/klmno/' and my sorry server is running a simple HTML page at '/apologies/apologies.htm' I have configured this directory and page to be the default, so I can hit the server directly at 'http://host.domain.com/' and get the correct content. I have tried a few different variations, and can't seem to be able to change the URI after 'when LB_FAILED' before the request goes to the apologies pool.

Rev 1, I added some logging to see what was being passed 

 
 when LB_FAILED { 
 log local0. "URI is [HTTP::uri]" 
 log local0. "$poolname has [active_members [LB::server pool]] members" 
 log local0. "URI is [HTTP::uri]" 
 pool pool_apologies_http 
 log local0. "Directed to pool [LB::server pool]" 
   }

Rev 2, tied the HTTP::uri command 

 
 when LB_FAILED { 
 log local0. "URI is [HTTP::uri]" 
 log local0. "$poolname has [active_members [LB::server pool]] members" 
  HTTP::uri "/" 
 log local0. "URI is [HTTP::uri]" 
 pool pool_apologies_http 
 log local0. "Directed to pool [LB::server pool]" 
   }

Can I do this with the 'when LB_FAILED' command, or does it have to be HTTP_REQUEST??

Thanks,

-L
application delivery
dev
devops
iRules
  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    Oct 24, 2008
    It looks like there are two instances of the directory in the path:

     

     

    /Library/controller/e/web/Portal/en/maintenance_files/maintenance_files/main.css

     

     

    Aaron
  • Leslie_South_55's avatar
    Leslie_South_55
    Icon for Nimbostratus rankNimbostratus
    Oct 25, 2008
    OK, found the issue. I modified the maintenance.htm file so that ever reference to 'maintenance_files/main.css' or other objects now looks like '/maintenance_files/main.css' looks like without the preceeding / the path was relative. After making this change, the page appears correctly. I will post the final rule soon, after I do some more testing.

     

     

    Thanks Aaron for your diligent efforts.

     

     

    -L
  • Sridhar_111831's avatar
    Sridhar_111831
    Icon for Nimbostratus rankNimbostratus
    Jun 30, 2011
    Leslie,

     

     

    I'm also having same requirement. I'm did not understand what you did to the page to fix the issue?

     

     

    Could you explain?

     

     

    Regards,

     

    Sridhar
  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    Jul 01, 2011
    You can create a /maintenance.html page in the application, add any content the maintenance.html page references under a /maintenance/ directory, add the maintenance server(s) to a pool named pool_apologies_http and then use this iRule: 

       when LB_FAILED {   
      
      log local0. "[IP::client_addr]:[TCP::client_port]: Request for [HTTP::uri] from Referer '[HTTP::header Referer]' to pool failed, [LB::server pool]"   
      
       Check if this request was not generated from the maintenance page using the HTTP referer header   
      if {not ([HTTP::path] contains "/maintenance_files/")}{   
      
         log local0. "[IP::client_addr]:[TCP::client_port]: Referer wasn't the maintenance page.  Rewriting URI to maintenance page."   
         HTTP::uri "/maintenance.htm"
      }  
      
       Send request to the apologies pool   
      LB::reselect pool pool_apologies_http   
      log local0. "[IP::client_addr]:[TCP::client_port]: Reselecting member from the apologies pool"   
   }

    Aaron