SMTP Loadbalance by Connection

[Andrew MacDonald]

I have configured my ACE to loadbalance SMTP between two mail servers. I want it to loadbalance by connection as all of the mail will be coming from one ip address. This is my current configuration.

access-list allow line 8 extended permit ip any any

probe tcp SMTP_PROBE
  port 25
  interval 5
  passdetect interval 5
  receive 3
  connection term forced
  open 2

rserver host mail1
  ip address 10.0.14.11
  inservice
rserver host mail2
  ip address 10.0.14.12
  inservice

serverfarm host SMTPFARM
  probe SMTP_PROBE
  rserver mail1 25
    inservice
  rserver mail2 25
    inservice

class-map match-all SMTP-CLASS-MAP
  2 match virtual-address 10.0.14.8 tcp eq smtp

policy-map type loadbalance first-match SMTP
  class class-default
    serverfarm SMTPFARM

policy-map multi-match SMTP-SLB
  class SMTP-CLASS-MAP
    loadbalance vip inservice
    loadbalance policy SMTP
    loadbalance vip icmp-reply active
    nat dynamic 1 vlan 100

interface vlan 100
  ip address 10.0.14.9 255.255.255.0
  access-group input allow
  nat-pool 1 10.0.14.8 10.0.14.8 netmask 255.255.255.255 pat
  service-policy input SMTP-SLB
  no shutdown

ip route 0.0.0.0 0.0.0.0 10.0.14.1

snmp-server community company group Network-Monitor

What do i need to do to make this happen?

Thanks!

-Andy

[Kanwaljeet Singh]

Hi Andrew,

If all the emails would be coming from IP address then you would need to consider L7 based loadbalancing. You can use cookie method to ensure stickyness. If your server inserts cookie you can make ACE to learn the cookie and if you want ACE to insert the cookie you can configure it to insert the cookie.

Regards,

Kanwal