How send a string to a specific IP's specific port when all pool members of a VIP are down?

Hi Johnson,

 

 

I wonder if you could check for [active_members [LB::server pool]] == 0 in CLIENT_ACCEPTED. If it is true, then collect the TCP payload with TCP::collect, replace all of it with TCP::payload replace and then select a new destination IP:port with the node command. Here are the wiki pages for the related commands:

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/lb__server

 

http://devcentral.f5.com/wiki/default.aspx/iRules/active_members

 

http://devcentral.f5.com/wiki/default.aspx/iRules/tcp__collect

 

http://devcentral.f5.com/wiki/default.aspx/iRules/tcp__payload

 

http://devcentral.f5.com/wiki/default.aspx/iRules/node

 

 

Aaron

Aaron: That sounds plausible, actually. You couldn't use LB::server pool in CLIENT_ACCEPTED really, since no pool would have been selected yet, but you could certainly use active_members if you know the specific pool anyway.

Something like (very untested):

when CLIENT_ACCEPTED {
  if {[active_members yourpoolname] == 0 } {
    TCP::collect
  }
}

when CLIENT_DATA {
  TCP::payload replace 0 [TCP::payload length] "down"
  node 10.10.10.1 12000
  TCP::release
}

Worth a shot at least. Try it out on a test VIP first as it's not tested, but that's the general idea.

Colin

[LB::server] and [LB::server pool] will return the virtual server's default pool name until a load balancing decision has been made. Once a load balancing decision has been made, [LB::server] will return a Tcl list with pool, node addr and port.

 

 

I think it was Unruley who pointed this out originally a while back. It makes for a simple way to avoid having to hard code the default pool name in iRules.

 

 

Aaron