Forum Discussion
Erki_Märks_2779
Nimbostratus
Nimbostratusdrain connections
There are two virtual servers, each have 1 pool with 2 nodes attached to it. The IP addresses of these nodes are the same for both of the pools, only port numbers differ. One node for instance 1.1.1.1 is primary and 1.1.1.2 is the secondary in each of these pools. The application is built so that it connects to the server logs in and the connection remains open. If 1.1.1.1 xx goes down, all connections should go to 1.1.1.2 and connections to 1.1.1.1 should be dropped. For that reason, the action on svcdown is set to drop on both of those pools, but even if i do LB::down and LB::down pool xxx member x.x.x.x xx, the connections stay open. Is there a way to do b conn server 2.2.2.2:80 delete from an irule.
when RULE_INIT
{
if {not([array exists ::arr])}
{
array set ::arr {
"primary" "1.1.1.1"
"secondary" "1.1.1.2"
}
}
}
when CLIENT_ACCEPTED
{
set port "xxxy"
set pool "pool_$port"
set portsec "xxxx"
set poolsec "pool_$portsec"
if { [active_members $pool] > 0 && [array exists ::arr] && [info exists ::arr(primary)] }
{
set secondary "$::arr(secondary)"
set primary "$::arr(primary)"
if {[LB::status pool $pool member $primary $port] != "up" && [LB::status pool $pool member $secondary $port] == "up"}
{
LB::down pool $poolsec member $primary $portsec
set ::arr(primary) "$secondary"
set ::arr(secondary) "$primary"
}
pool $pool member $::arr(primary)
}
else
{
reject
}
}
when LB_FAILED
{
LB::down
LB::down pool $poolsec member [LB::server addr] $portsec
if { [LB::server addr] == "$::arr(primary)" && [active_members $pool] > 0 }
{
if {[LB::status pool $pool member $::arr(secondary) $port] == "up"}
{
set ::arr(primary) $::arr(secondary)
set ::arr(secondary) [LB::server addr]
pool $pool member $::arr(primary)
}
}
}
9 Replies
- Well, first of all there are a lot of optimizations I would suggest for your iRule to make it more efficient. Setting variables where they aren't absolutely required, using global arrays rather than static:: values (assuming you're on a version that supports them), etc. If you're interested in an optimization discussion, let me know and I'd be happy to help out in that arena.
More to your point, however, have you tried using the LB::detach command? Click Here
If what you're trying to do is convince the LTM to disconnect from the pool member that'd be the best way to do it, I think.
Colin 
Erki_Märks_2779I would only think that i need to use global arrays because i use this data globally - there's at least two of those irules one attached to vhost1, the second irule to the second to vhost2.
For ease of use, the only things that are modified are:
set port "xxx"
set pool "pool_$port"
set portsec "yyy"
set poolsec "pool_$portsec"
vhost1
pool_xxx
node 1.1.1.1 xxx
node 1.1.1.2 xxx
vhost2
pool_yyy
node 1.1.1.1 yyy
node 1.1.1.2 yyy
if node 1.1.1.1 xxx is standby, then node 1.1.1.1 yyy should be standby. If node 1.1.1.2 xxx () goes down, 1.1.1.1 is set to active and so the connections to both of the virtual servers must be dropped and new connections initiated so that the programs are connected to and will log in to 1.1.1.1 yyy and 1.1.1.1 xxx.
What i'm trying to implement is a basic functionality of a fail-over cluster. The bad thing is that even if the action on svcdown is set to drop the connections are not dropped if I do LB::down.
I think LB::detach is not an option because the programs are connected to the server and waiting some data. Unless there's no data sent i can't even use when SERVER_DATA to do TCP::close or something like that.- Erki_Märks_2779any thoughts?
- JRahm
Admin
I think you could eliminate a lot of complexity by collapsing the two pools into one and attaching a monitor for both ports to the pool. That way, if there's a failure to your node supporting both ports, they both go down. - Erki_Märks_2779That's a good idea, but what about the problem that the connections are not dropped, how could i solve this
- JRahmTCP::close should close the connection
- Erki_Märks_2779I know that TCP::close closes the current connection but how could I drop all the connections to both of those vhosts at once. As I said setting pool action on svcdown to drop didn't help me.
- JRahmIf the monitor is marking the pool members down, the connections should be closed automatically. I don't think you can close all connections from an iRule that is only concerned about the current connection, but I could be wrong about that.
hoolioCirrostratus
If you have a monitor for both ports associated with the pool member, have action on service down set to reject and either port goes down, LTM should send a reset for any open connections for either port.
Aaron
