How do I bind Postfix MTA to specific IP address such as 127.0.0.1 or 22.214.171.124?
Q. I’ve recently changed email user account password using passwd command, for one my postfix email server which requires SMTP authentication before sending an email. Now following error is logged into my /var/log/maillog file:
ERROR: Password not accepted from server: 535 5.7.0 Error: authentication failed: authentication failure
How do I solve this problem under Red Hat enterprise Linux running Postfix with SASL authentication?
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Q. We have decided to move to Linux and brought a dedicated Dell server preinstalled with Red Hat Linux for hosting our small business website. Can you tell me what software required to run on a Linux dedicated server for hosting purpose?
Q. My mail delivery fails with DNS: Service unavailable error. How do I fix this error under Linux / UNIX operating systems?
Q. Can you tell me more about Linux Demilitarized Zone and Ethernet Interface Card Requirements for typical DMZ implementation? How can a rule be set to route traffic to certain machines on a DMZ for HTTP or SMTP?
A. Demilitarized zone, used to secure an internal network from external access. You can use Linux firewall to create DMZ easily. There are many different ways to design a network with a DMZ. The basic method is to use a single Linux firewall with 3 Ethernet cards. The following simple example discusses DMZ setup and forwarding public traffic to internal servers.
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