User sessions getting timed out

We are having some issues with some applications that were recently migrated to ASM. The developers have been complaining the sessions are getting timed out. Our ASM only has light LTM and is not a fully balanced LTM and we don't load balance on ASM. Our virtual server points to SNAT pool of LTMs and then LTM further has a SNAT to the NAMs(Novell Access Manager) and then the app.

See how sessions get different NAM IPs

DEBUG - 2018-04-25 08:50:54 --> SESSION: sessionid 1.1.1.1 vs 10.10.10.10 ip not matching, but we will not destroy it.

DEBUG - 2018-04-25 08:51:11 --> SESSION: sessionid 11.1.1.1 vs 10.10.10.10 ip not matching, but we will not destroy it.

DEBUG - 2018-04-25 08:51:14 --> SESSION: sessionid 1.1.1.1 vs 10.10.10.10 ip not matching, but we will not destroy it.

DEBUG - 2018-04-25 08:51:15 --> SESSION: sessionid 1.1.1.1 vs 20.20.20.20 ip not matching, but we will not destroy it.

DEBUG - 2018-04-25 08:51:17 --> SESSION: sessionid 1.1.1.1 vs 20.20.20.20 ip not matching, but we will not destroy it.

The following irule fixed the issue but curious to know how to know which applications will need this and which wont and are there any other known issues with using this irule. Thanks in advance for all your help on this !

when HTTP_REQUEST { if { ![info exists static::array_size] or ![array exists static::snat_ips] } { unset -nocomplain static::snat_ips

    set snatpool_name "/Common/my_snat_pool"
    set members_cmd "members -list $snatpool_name"

    set count 0
    foreach snat_ip [eval $members_cmd] {
        set static::snat_ips($count) [lindex $snat_ip 0]
        incr count
    }
    set static::array_size [array size static::snat_ips]
}

snat $static::snat_ips([expr {[crc32 [IP::client_addr]] % $static::array_size}])

}