Maintenance Page using V11

So two things:

1. If you were using images in your maintenance page, the image ifiles would be in whatever image format, and the html page ifile would be a text file. In most cases you also want to include the "Content-Type" header in the response so the browser knows how to handle the object.

2. Since you don't have any images in your maintenance page, the iRule is considerably simpler:

   when HTTP_REQUEST { 
       if { [active_members [LB::server pool]] < 1 } { 
           HTTP::respond 200 content [ifile get "maint_index_html"] 
       } 
   }