Forum Discussion
Nimbostratussmtp outgoing load balancing
I have /28 16 ip addresses and then want to use them as my MX records. I have 2 real smtp servers that will send mail to outside and accept mail from outside while load balancing these 16 ips. I tried to do somethings with my own but outbound sending was unsuccessful. I created a virtual server with that my smtp servers can talk from port 25 and then created an snat pool with these ips connect it to this VS and I did not put any pool for the VS and it did not work. What should be the right config for this request in F5 LTM?
12 Replies
What_Lies_Bene1Cirrostratus
Not sure I understand about the 16 IPs but regardless, for the outbound you should use a separate wildcard VS (only enabled on the relevant internal VLAN) listening on port 25 and attach the SNAT Pool to that.
- nitass
Employee
you mean you want to snat source ip to /28 16 ip addresses for outbound email from 2 smtp servers and accept inbound email destined to /28 16 ip addresses then load balance to 2 smtp servers, don't you?
edib_26117yes, a virtual server with 16 ip address or 16 virtual server and 2 pool member to accept smtp incoming, I have succesfully achieved it. But I cannot achieve sending email. I defined an virtual server with ip address ie 192.168.0.3, my members servers are 192.168.0.4-5 and I put real 16 ips snat into 192.168.0.3 VS. but then I cannot figured it out how to redirect mail traffic to 192.168.0.3 port 25.
nitass_89166Noctilucent
you mean you want to snat source ip to /28 16 ip addresses for outbound email from 2 smtp servers and accept inbound email destined to /28 16 ip addresses then load balance to 2 smtp servers, don't you?
- edib_26117yes, a virtual server with 16 ip address or 16 virtual server and 2 pool member to accept smtp incoming, I have succesfully achieved it. But I cannot achieve sending email. I defined an virtual server with ip address ie 192.168.0.3, my members servers are 192.168.0.4-5 and I put real 16 ips snat into 192.168.0.3 VS. but then I cannot figured it out how to redirect mail traffic to 192.168.0.3 port 25.
- nitass
I defined an virtual server with ip address ie 192.168.0.3, my members servers are 192.168.0.4-5 and I put real 16 ips snat into 192.168.0.3 VS. but then I cannot figured it out how to redirect mail traffic to 192.168.0.3 port 25.
as Steven mentioned, you should create wildcard forwarding virtual server listening on port 25 (0.0.0.0/0:25) and assign snatpool (/28 16 ip addresses) to it.
- nitass
how can mail servers (pool members) route the mail traffik to this virtual server?
isn't smtp server default gateway bigip?
- edib_26117ok, I understand now. If I make default gateway of the members the bigip, then everything fits. At first without default gateway, I tried to solve it. but it seems that I must do that. thanks.
- What_Lies_Bene1Cool. Let us know if it works (or not).
- nitass_89166
how can mail servers (pool members) route the mail traffik to this virtual server?
isn't smtp server default gateway bigip?
- edib_26117ok, I understand now. If I make default gateway of the members the bigip, then everything fits. At first without default gateway, I tried to solve it. but it seems that I must do that. thanks.
- What_Lies_Bene1Cool. Let us know if it works (or not).
