Using CSM to load-balance two sites

Question

Hi there,
I currently use CSS11500's at two of my sites and I'm able to use source-groups to achieve site load-balancing behind a single VIP.  So basically I have a VIP that has servers in both the local site and remote site.   Is something like this possible with the CSM? I suppose there's the nat server or nat client commands, but I'd like to be able to maintain original client IP address if possible, or at least maintain the original client IP for connections that stay local to the site.
Thanks,
Brandon

Answer 1

Hello Brandon-
It is not directly possible to pick and choose what servers are natted on the CSM like the CSS and ACE can do.
In the CSM, you configure nat under the serverfarm specifically.
Ex.
serverfarm Client_Nat_Example
nat server
nat client REMOTENAT
real 10.10.10.1
  inservice
natpool REMOTENAT 172.16.35.5 172.16.35.5 netmask 255.255.255.0
If you were to devide up the traffic prior to hitting a serverfarm (maybe use a policy that matches specific subnets for your clients), then you could nat to only certain servers.
Ex.
access-list 2 permit 5.5.0.0 0.0.255.255
serverfarm Client-Nat-Example
nat server
nat client REMOTENAT
real 10.10.10.1
  inservice
serverfarm No_Nat
nat server
no nat client
real 20.20.20.1
  inservice
natpool REMOTENAT 172.16.35.5 172.16.35.5 netmask 255.255.255.0
policy client_remote
serverfarm Client_Nat_Example
client-group 2
vserver HTTP
  virtual  172.16.35.7 tcp www
  slb-policy client_remote
  serverfarm No_Nat
  persistent rebalance
  inservice
With this config, the CSM checks global access list 2, anything that matches a source of 5.5.x.x subnet would go to the serverfarm with the remote servers. Anything that does not match 5.5.x.x would use the default serverfarm under the vip (No_Nat serverfarm).  This is not optimal, but there is no parity between CSM and CSS when it comes to per-server NAT.