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Forum Discussion

pgopparaju's avatar
pgopparaju
Icon for Nimbostratus rankNimbostratus
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...
AFM
application delivery
BIG-IP
iRules
LTM
pgopparaju's avatar
pgopparaju
Icon for Nimbostratus rankNimbostratus
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.

Kevin_Davies's avatar
Kevin_Davies
Icon for Nacreous rankNacreous
Jun 11, 2019

What profiles do you have attached to the VS?