We have sendmail running in a RHEL box. We have two public IP address configured in the same box, one for SAP app and other for Sendmail. First interface will be used for SAP and second for Sendmail.I have binded the Sendmail daemon on secondary NIC, but when I send out a mail, traffic is getting initiated via the primary NIC and connection is getting refused as port 25 is blocked for the this NIC in the firewall.Can someone please help me out to resolve this? Should I make changes in Sendmail's config to route SMTP traffic via secondary NIC, or should I play with IPtables to get this done? I need some ideas.Thanks in advance for the reply.ChristopherAs requested:$ route -nKernel IP routing tableDestination     Gateway         Genmask         Flags Metric Ref    Use Ifacexxx.x.x.32      0.0.0.0         255.255.255.240 U     0      0        0 eth110.90.9.96      0.0.0.0         255.255.255.224 U     0      0        0 eth00.0.0.0         xx.x.x.33       0.0.0.0         UG    0      0        0 eth1
How to initiate SMTP outbound traffic via secondary interface - Linux Sendmail
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