finding the IP address of another computer

[lifto]

OK, here is the deal. I have 2 win2k machines on a hub that is connected to a cable modem. Each machine is running IP and pulling an IP address from DHCP along with netBeui. I'm at machine1 and I want to use VNC to access machine2. VNC runs on IP so I need the IP address of machine2. Is there an easy way to get it while sitting at machine1.

thanks

 

[Provogeek]

Normally, if you query the computer name, you can get the IP address.

do you have a gateway server in place by any chance? If you do, then it would just be the next Ip in the DHCP range the gateway provides.

BUT

If you just have a hub between you and the cable modem, then chances are, each computer is on a different subnet. I ran into this problem on my home network before I got a gateway router. Since they limit you to just 128k upload, you will have slow speeds to do any file transfers or VNC because all traffic will route to the cable providers network, go through their switches and routers before comming back to your home network, sounds pointless right? Thats why I got the gateway router, allows my PC's to be on the same subnet that is in my control.

Provogeek

Saving the world, one network at a time

 

[bcastner]

It is not a great idea to have the two machines "pull" an external IP and use that in addition as private LAN side addresses.

Netbui does not route, nor is using external IPs and WAN and DNS to resolve essentially private LAN addresses sensible.

While your message is a little confusing, I am confident that replacing the hub with a router for ~$40 would allow you to handle LAN and WAN side issues in a better form than you are trying currently. There are no advantages to you in terms of speed from your two IPs; you are sharing a single modem connection on a single cable segment.

Throw out the hub (a 10 mb-half duplex appliance) and replace it with a router/switch (a 100 MB-Full duplex LAN side appliance) and use a single IP.

 

[gunthnp]

vnc can run by computer name type it in should open a vnc conntection try pinging the name and you will get back the
ip address

gunthnp

 

[bcastner]

gunthnp,

You have left several messages promoting VNC in different forums.

It is a decent remote client. But perhaps you should read this Gentleman's question first. He is on a cable system on the same headend. VNC would not work in his circumstance.

Your unbridled enthusiasm for VNC would be better served if they matched the fact of restrictions on the headend routers of cable systems.

 

[Provogeek]

Actually, VNC would work under this circumstance.

HOWEVER, VNC would not be able to resolve host name to an IP address when the host is on a different subnet.

And actually, no one has answered lifto's question. We have only offered our advice as seasoned network engineers and techs. Useing a gateway router with broadband Internet access on a cable medium is just an easier way to do a home network and provide all computers on your home network with client access to the Internet AND be on the same subnet.

To actually answer lifto's question, no, there is no way you can obtain your second PC's IP address with out using network scanning tools. Using such tools on braodband service providers networks such as Comcast will get your account disabled if you do an intrusive scan. Any type of scan done will take longer to find your second PC's IP address than it would take you to get up and run IPCONFIG on your second machine your self.

Provogeek

Saving the world, one network at a time

 

[gunthnp]

bcaster I was just refering to lifto comment about vnc can not reslove names when it can

but it sounds like both computers are on the same subnet and there for if he know the name of the other computer all he has to do is ping the other computers name and he will get back the address with netbios on but I do not recommand leaving netbios on, on a cable network

gunthnp

 

[Grenage]

The Only solution I can think of might be a Dynamic DNS service on the machine you wish to VNC to. If you have not used one of these before, you install a small client on your machine which you configure to use one of the many freely available Dynamic DNS Services available.

Every time you connect to the internet on this machine, it the client contacts the service host and tells them your IP. Now when you sign up for the service they will give you a name such as USERNAME.DyDNS.com, this is your IP alias for your machine. Basically you can then connect to USERNAME.DyDNS.com ad whatever IP address your machine has it will connect to it.

So you could use one of these services and use USERNAME.DyDNS.com in place of the machines IP address.

http://www.dyndns.org/

is one such place for this tool.

Hope that helped some.

 

[bcastner]

Provogeek,

No it will not work as the routing at the headend will block the connection.

 

[Provogeek]

There must have been a recent change in past few years on the broadband network that I am not aware of. It worked for me when the CA cable network was serviced by @Home. I tried it, it worked, it was slow, it sucked, so I got a gateway router.

That is the basis of my statment.

Provogeek

Saving the world, one network at a time

 

[lifto]

Thanks for the suggestions. Maybe there are a few things to clarify.

VNC will work across the internet provided you have the IP address of the remote machine. It won't work using the name of the remote machine because cable providers do not provide name to ip address resolution for individual connections. On a private network that provides name to ip address resolution, VNC gets the IP address from the computer name just fine.

Is there a way to query by mac address and get the ip address back?

 

[gunthnp]

not pass a router

gunthnp

 

[bcastner]

lifto,

I am with gunthnp. It should work. But because both IPs, even though WAN-side, are on the same subnet mask for the router it just will not work.

The router will kill it.

Look at some of the multi-player games sites for confirmation that using cable system IPs are not going to work if they fall within the same subnet mask.

sorry, Provogreek, your idea is a perfectly good one other than two sites on the same cable network with the same subnet mask applicable.