I'm trying to comprehend this situation that I'm in but I see that I'm confused for the most part.
There is a network which has a PIX on the edge point. It has an outside-if, 162.x.z.86, and inside-if, 162.x.x.1.
There is a mail server (lotus) on the inside segment of the PIX with an IP of 162.x.x.6 - the mail server also has an internal IP of 10.0.16.51 -- The external IP is registered with their hosting co as the MX.
A Barracuda spam filter has been installed as well, with an internal of 10.0.16.145
What I'm trying to do is have all SMTP requests that the PIX receives on the external to forward to the Barracuda, which by the way the PIX can ping so I know there's connectivity, and have the Barracuda hand them off to the Notes.
I've already setup the Barracuda to have the mail server as the lotus box.
On the PIX I've configured an access list to:
access-list allow_inbound permit tcp any host 162.x.x.6 eq smtp
access-list allow_inbound permit tcp any host 162.x.x.6 eq lotusnotes
access-list email_nat permit ip host 10.0.16.145
access-list email_nat permit ip host 10.0.16.51
nat (inside) 25 access-list email_nat 0 0
global (outside) 25 162.x.x.6
static (inside,outside) tcp interface smtp 10.0.16.145 smtp netmask 255.255.255.255 0 0
I assume that this configuration will have the internal of the Notes NATed to 162.x.x.6 when leaving PIX, and any SMTP will be routed to the internal of Notes.
I show some hits on the email_nat access list...
But I don't see Barracuda receiving emails, and I get this report as well when I perform a connectivity test from it:
Error: Supposedly valid email is being rejected by your mail server. Please verify your test email address, and configure your mail server to receive email for this address from the Barracuda Spam Firewall.
Error: It does not look like the MX record for your default domain resolves to your Barracuda Spam Firewall's IP address. Please verify that your DNS servers are properly configured.
Error: Could not send mail to your Barracuda Spam Firewall. Please verify that your network permissions (firewall) allow SMTP traffic from the Internet to the Barracuda Spam Firewall.
I hope I've provided enough information. Is there anyone who can assist me on this issue?