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Gabriell_141363's avatar
Icon for Nimbostratus rankNimbostratus
Jan 14, 2014

Route mode +Snat+servers belonging to the same pool on different subnet??

Hi community,


I wonder if the following scenario is possible:


Scope: Balance traffic among servers belonging to 2 different subnets.


Expect or guessed scenario:


External Incoming traffic hits active LB virtual server IP add (VIP+port) on Vlan 1 via routing. Active LB matches the traffic towards a pool of servers (being Server 1 is on subnet 1 and server 2 on subnet 2). LB Performs Snat and routes the traffic for example to server 1 (RR for instance) through the router (vlan 1 gw) and this performs nh routing towards destination server 1 IP address. Server 1 answers ip source via routing (Snat IP address belonging to the LB) The LB forwrdas the reply back to the external client with the former ip addreses (un doing the Snat).


Would that be possible? i mean, 2 servers balanced forming a farm on different nets.


Thansk a lot in advance. Gabriel.


3 Replies

  • Thanks for the good news. Platform area pair of 1500; is there anything we should be aware of?(Nat-Pat IP pools definition, latency, impact on routig ne besides routing itself... ) or even a best practice guideline if you know bout? both balanced servers (vlan1 and vlan2) are meant to be located on different sites




  • TMM doesn't care whether the pool members are all in the same VLAN or even if they are the same number of hops away - you can have pool members in directly attached vlans at the same time as pool members in a different site. The only thing would be....if the site is remote (as in significantly different latency between them), you could consider using priority groups to prefer pool members in the local site and only use pool members in the other site if only X (or less) servers available in local site.


    Also, you may need to use a SNAT, you may not - it depends on your network topology.