We are facing problem with the sendmail server when it is put behind the iptables firewall. The setup is: Sendmail 8.12.9 IPTables 1.2.7 Shorewall 1.3.14 Earlier Sendmail server was connected directly to the Internet with a valid Internet IP. At that time the number of sendmail processes never exceeded 10 at any given poing of time. (Checked with ps -ef | grep sendmail) Now we have implemented the Mandrake Linux 9.1 based firewall using IPTables and Shorewall. NATting was configured on the firewall. After doing this, we have observed that the number of sendmail process keeps on increasing and goes upto nearly 170 processes. It seems that the problem is with the incoming message requests. It process remains open for nearly 2 hours. This is observed for random connections or some particular sites. As such sendmail server is receiving and sending mails without any problem to the users. After I remove the firewall and put the server directly on the internet the sendmail processes remain at less than 10. I have been working on this problem for last two days without success. I cannot understand whether the problem is with the implementation of firewall (NATting) or with sendmail server. I have checked the firewall with only NATting (removed all the rules) Kindly help. Thanks and regards, Pradeep Bhomia
