Incorrect load balancing when disabling Oneconnect

Is the app-pool configured as Default Pool in your Virtual Server settings? If you conditionally select another pool, ie. the server-report1 pool in an iRule, you will need to include a 'Default or Else' clause in the iRule to 'Re-Confirm' your Default Pool. Just having the app-pool as your Default Pool setting in Virtual Server properties will not be enough.

You may see a similar problem occuring in your environment:

- Your first request to app-pool is routed correctly
- Your second request to app-pool is routed correctly
- .. All requests destined to app-pool are routed correctly, until the first occurence where a request is routed to server-report1 pool
- .. All the requests that should go to app-pool (default) thereafter are now incorrectly routed to server-report1 pool.

For a solution, if you're using the

if

else

switch

default

Give it a try, if the conditions described match your configuration. This would be a generic iRule problem, not related to OneConnect by any means.

Hi NiHo,

if you need to switch pools or persistence profiles without using a ONECONNECT profile, then you have to issue a

[LB::detach]

See the links below for further information...

https://support.f5.com/kb/en-us/solutions/public/7000/900/sol7964.html

https://support.f5.com/kb/en-us/solutions/public/9000/800/sol9800.html

https://devcentral.f5.com/wiki/iRules.LB__detach.ashx

BTW: You may also want to try the (experimental) syntax below, to implement a simple request flow mechanism, with the purpose to only detach the server-side connection and re-apply the pool settings when its required.

when CLIENT_ACCEPTED {
    set last_pool ""
}
when HTTP_REQUEST {
    if { [string tolower [HTTP::uri]] starts_with "/somepath" } then {
        if { $last_pool equals "my_pool_a" } then {
            do nothing
        } else {
            LB::detach
            pool my_pool_a
            set last_pool my_pool_a
        }
    } else {
        if { $last_pool equals "my_pool_b" } then {
            do nothing
        } else {
            LB::detach
            pool my_pool_b
            set last_pool my_pool_b
        }
    }
}

Cheers, Kai

Hi,

In irule changing the pool based on URI, don't forget to change back to default pool URI which does not match specific URI.

Pool decision is done for the entire tcp connection when one connect is not enabled.

when CLIENT_ACCEPTED {
  set default_pool [LB::server pool]
}

when HTTP_REQUEST {
    if {[HTTP::uri] starts_with "/reports"} { 
        pool report
    } else {
        pool $default_pool
    }
}