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help...seeing web server from anywhere on the internet

Started by Max July 17, 2005
there is one simple matter I can't figure out.  If I connect an
ethernet enabled micro to my home network and assign it
an IP address I can access its web server from my PC.
But, my firewall has it's own IP address assigned from my
ISP...How do I access the micro from outside, somewhere
else on the internet?
(I tried searching for the answer but came up with a million
unhelpful links)

Thanks,
Max


Hi Max,

The fact that its a micro is irrelevant.  This is no different than any
other networkable device inside your firewall.

In order for the device to see out you have to enable your firewall to
let packets out and do some masquerading (assuming you only have one IP
number).  So every computer on your internal network will have the same
IP number as your firewall (this is assuming that the computer that
connects to the internet and the firewall are one and the same--this
doesn't have to be the case).

In order to receive packets you need to configure the firewall to
forward packets to certain ports to your device.

Look for home networking how-to's.  There are lots available for Linux
and are useful even if you're not using Linux to understand how it all
works.

Hope that helps.

James.

On Sun, 2005-07-17 at 03:37 +0000, Max wrote:
> there is one simple matter I can't figure out. If I connect an > ethernet enabled micro to my home network and assign it > an IP address I can access its web server from my PC. > But, my firewall has it's own IP address assigned from my > ISP...How do I access the micro from outside, somewhere > else on the internet? > (I tried searching for the answer but came up with a million > unhelpful links) > > Thanks, > Max > >
Max wrote:
> But, my firewall has it's own IP address assigned from my > ISP...How do I access the micro from outside, somewhere > else on the internet?
Two options: a) install your appliance on your firewall's DMZ b) configure your firewall's "port forwarding" to forward inbound packets to the firewall port X to the appliance's web server port Kelly
Max wrote:
> How do I access the micro from outside, somewhere > else on the internet?
Using a Linksys firewall as an example... Go to the UPnP Port Forwarding tab. Enable port 80 on the outside to forward to port 80 on your device's inside IP. Note that your ISP may not allow hosting, and may block inbound connections to certain ports like TCP25 (mail) and TCP80 (http). You can get around this by setting a different outside port number. The URL then looks like http://169.254.1.1:1234 for port 1234. In fact, it's probably a good idea not to use port 80, as it'll be probed / attacked regularly by scanners. (And even if your ISP doesn't block port 80, they may nail you for AUP violation they find something on port 80.) Cheers, Richard
In article <_nkCe.114217$HI.22719@edtnps84>,
	"Max" <dontlikespam@yahoo.com> writes:
> But, my firewall has it's own IP address assigned from my > ISP...How do I access the micro from outside, somewhere > else on the internet?
Besides the part of configuring your firewall to let http requests get through to your appliance, wich has been explained by the other reponders, there is also the issue of your ISP assigning a new and probably different IP address each time your firewall makes a connection. You probably want to access your appliance under a constant URL rather than having to keep track of the IP address of the day. To do this, there are free services available (for instance, look at www.dyndns.org) for dynamic name resolution. You first register a domain name with them and then you usually install a client on your firewall that transfers the current IP address to the dyndns name server each time your firewall makes a new connection. Rob -- Robert Kaiser email: rkaiser AT sysgo DOT com SYSGO AG http://www.elinos.com Klein-Winternheim / Germany http://www.sysgo.com
thank you to each of the responders, I learnt something from each
post.  I have a D-Link router and I ended up using the Virtual
Server capability.  I set up a new entry that tied my private
IP address and private port (80) to a public port 1234.
And, it works!
  My IP address stays the same (at least for a while at a time)
but I am going to play around with the dynamic name part
as mentioned by Robert.
Thanks again...
M

> there is one simple matter I can't figure out. If I connect an > ethernet enabled micro to my home network and assign it > an IP address I can access its web server from my PC. > But, my firewall has it's own IP address assigned from my > ISP...How do I access the micro from outside, somewhere > else on the internet? > (I tried searching for the answer but came up with a million > unhelpful links) > > Thanks, > Max > >

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