Port Forwarding and DNS

[Roy Arends]

On Fri, 14 Apr 2000, Jan Devos wrote:

> I use an ADSL line with one static ip-address, and adsl-router (+ hub) and a
> couple of servers (mail, http, ftp) using port-forwarding.
> (http://www.ml1.org)
> 
> I have two questions.

You have four questions ;-)

> 1) Is it possible to have multiple ip-addresses using 1 ADSL-line (and a
> router)? Where can I buy extra ip-addresses (± 10) besides my isp?

1a. Yes
1b. In general, nowhere. ISP's have specific ip-spaces, 'loaned' to them
    by ARIN, RIPE or APNIC. They are not allowed to route any packets with
    (source or destination) addresses other then from their own
    address-pool. 
    You have 3 options, next to port-forwarding.
    1. Contact your own ISP, ask'em to allocate 10 ip-addresses.
    2. Buy another connection from a different ISP, ask them to allocate
       10 ip-addresses.
    3. Use private-space addresses. (see RFC 1918) This is also very handy
       when you switch ISP.

> 2) Can I set-up a dns server using port-forwarding and what ports should I
> forward to the dns-server?

2a. I don't see any problems with that.
2b. port 53 (tcp/udp)

> Greetings,
> Jan Devos
> mailto:webmaster at go4host.com

Regards,

Roy Arends
-- 
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