Forum Discussion

Nimbostratus

Jun 10, 2019

Blocking specific hostnames to send emails through SMTP Realy

Hi, We use F5 BIG-IP as the SMTP relay and need assistance in blocking specific hostnames to send out emails, i did went through some iRules but couldn't find anything that can help me with and...

Nimbostratus

Jun 11, 2019

Hi Kevin,

overview of our setup :

we have a virtual server(SMTP relay host) created on port 25 with a pool of gmail SMTP servers , this virtual server is NATED to an external IP on our edge firewall with SNAT enabled on the F5.

our internal applications are pointed to the relay hostname on the F5 and we want to restrict specific client(applications) hostnames SMTP traffic to be dropped on the F5 before forwarding that to the pool members.

hope i made it clear.

Thanks in advance.