Hi! I'm a newbie at networking in general and at configuring Linux services in particular.

I have an SDSL connection from an ISP, where my router has a fixed address on the internet and the network on my side of the router is a subnet, with an address range 192.168.1.0 through 255. I think I grasp that. I'm having trouble with Email and DNS services, which may be due to my not fully understanding (a) some missed details about subnets that I should know and (b) some points about my router's IP address.

I have a Linux box, which I want to use as a web server and as an email server. I have managed to configure Postfix successfully, so that I can send email to user accounts on this box and also send messages out to internet addresses. But, I cannot reply back to my domain from an internet address.

I registered [mydomain.com] with Network Solutions and listed the world IP address of my router as the primary nameserver. I figured that was one step in the right direction toward making my domain "visible" for sending in email and for facilitating www browsing. Was that the correct thing to do? The more I think about it, I wonder: do I need DNS?

What I want is the following: any mail addressed to user@[mydomain.com] to get delivered to my Linux box, whereupon it gets delivered to users within that domain, subject to filtering I setup on this Linux box. Also, any calls for www.[mydomain.com] should find the www pages setup on this box. In order for those things to happen, should I be trying to setup DNS on my own?

If you haven't guessed by now, I'm completely lost and the HOWTO's aren't helping. I'd appreciate it if somebody could explain or point me to a good beginner's tutorial (that uses idiotic examples and illustrations ) on networking, subnets and public services.

It's been a month and I still don't get it! I'm normally a pretty quick study...

I'd suggest you use Network Solutions DNS servers. They probably have a somewhat configurable setup.

I am registered through Regiser.com and I use their nameservers. Their configuration lets me modify my IP (A Record), Domain Alias (C Record), and mail exchange (MX). I'm sure NS offers a similar configuration.

You can setup your IP like:
*.mydomain.com ipaddress ( not needed if using alias )
mydomain.com ipaddress

and/or

www.mydomain.com ipaddress
ftp.mydomain.com ipaddress

Since you only have one Internet IP address you will have to use Apache's Virtual hosts feature if you want multiple names to access the same webserver:
www.mydomain.com
test.mydomain.com
ww2.hellodude.com (register a second name)

I also have my own email server that works fine.
dude@mydomain.com

I'd advise against running your own DNS server. You really need a backup as well, requiring a second IP address.

Make sure you setup a firewall!

Hope this helps

Thanks! I'm making progress, though I couldn't begin to explain it if you asked me!

How do I identify my firewall or tell if it is running? I have configured the Bastille-firewall.cfg file, but I can't tell if the firewall is actually running.

Thanks!

You can view your rules with:
But to really test test it I'd suggest beating on it from the internet.