public ip -hanging the network

[dinakar]

sir we are having one public ip & we registered some name
like abc.net , & we routed the ip with that name , all these done by
some web server providers .upto now all are fine but when we are giving this
ip & name togeather to our mail server system (internal) its creating unnecessary
bandwidth (that causing our network sluggish , our router gets haged etc)
when ever i remooved that system into my network i am getting my network fast
(fine working ). what might be the problem
i had tried the windows xp , windows 2000 prof,
windows 200 server & linux as our mail servers
all are getting the same error
plz help me in this issue

[Dangerous]

Hi Dinakar,

Basically you are saying you have a domain name and public IP, which when entered into your mail server causes your network traffic to increase hugely?

Can you answer these questions please:


When you say "internal" mail server, do you mean you are hosting the server yourself?
What mail server software are you using to do this (I know you mentioned it happens on any O/S, but what is the main software)
Is your network protected by a firewall and if so, is this mail server on the demil (unprotected) zone?
Does the traffic increase start the moment you enter the IP & domain name details?


I think you should check that the mail server is not set to act as an open relay server.

D

[dinakar]

1.ya we want to host our own mail server
2.IIs , communigate pro , sendmail etc i have used uptonow
3.we dont have any firewall
but the mail server ran 3 months smoothly
after that we got this problem
the traffic is increasing not immediately after entering the ip & domain name
its taking 2 to 3 hrs
but the congession is reducing immediately by plugging off the server
i hope i have answered all of ur questions
thanks for ur time
plz suggest me a solution

[Dangerous]

Hi Dinakar,

Typcially, when people host a mailserver it is installed on an unprotected part of their network, the other "side" of the network which has all the servers and client machines is protected by a firewall.

I am by no means an expert in this area but have set up and run my own mail servers before, it sounds very much to me as if you have an open relay mail server sitting on your network. And because there is no protection (firewall filtering network packets) between the mail server and the rest of your network, you are wide-open to all sorts of chaos. (This is not an expensive piece of kit nowadays. You could survive with an old PC which has two network cards in it, and a copy of Linux if you don't have the money for the firewall)

I would strongly suggest you get hold of a hardware firewall and install it on your network. It needs to sit between your network and internet connection, with the mail server on the "optional" or "Demilitarised" port on the firewall. (This will all make perfect sense when you look into firewalls!)

I assume the mail server actually works correctly when it is on? It just grinds the network to a halt after a little while?

David.

(PS: If you need advice / info on firewalls, reply to this thread)

[dinakar]

which is better hardware /software firewall , & name them like linksys,zonealaram like that , if u prefer some thing i ll discuss with my tech , purchases managers & take a desicion on it
thanks for ur time