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Don_22992's avatar
Don_22992
Icon for Nimbostratus rankNimbostratus
Dec 09, 2009

SMTP Load Balancing and Routing

I have two SMTP mail servers. I need to load balance them for an internal network, so that they may both send SMTP outbound. However, due to some application restrictions, I only want inbound SMTP to ...
config
design
hooleylist's avatar
hooleylist
Icon for Cirrostratus rankCirrostratus
Jan 20, 2010
Hi Don,

 

 

SNATs, by definition only allow outbound connections. So a client cannot connect to a SNAT address. Only a host "behind" the SNAT can use the SNAT to initiate traffic. If the SNAT is assigned to the VIP, then only the connections through the VIP use the SNAT.

 

 

I would avoid NATs as they're liable to cause conflicts if they're configured on the same address as other objects (not that you've done this). You can generally get more specific control by using VIPs as VIPs can be port and protocol specific.

 

 

Here are a couple of solutions which describe SNATs and NATs:

 

 

SOL108: NAT and SNAT

 

https://support.f5.com/kb/en-us/solutions/public/0000/100/sol108.html

 

 

SOL7820: Overview of SNAT features

 

https://support.f5.com/kb/en-us/solutions/public/7000/800/sol7820.html

 

 

Aaron