2 comps get same automatic IP in network....

[Alex]

UPDATED! SOLVED!!!
see last post! thx to all who posted you guys really helped me out a lot!!

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so for the longest time i've been trying to get our 2 new xp boxes to work on our office workgroup but only 1 ever works at a time and its really odd and after checking it out i found out that they both are being assigned the exact same IP automatically.

we use a 16port Linksys switch and our DSL modem has a built in NAT router so there's no need for a server and we just use a workgroup config.
the 2 xp systems are absolutely identical, same mobo, same processor, same ram, same HD, the only difference is one has a cd burner and the other just has a regular cd reader.

earlier on today i tried manually setting the IPs for these two computers and they stayed different, but they both lost internet access (weird) and they could 'see' all other comps in the network but still not eachother.

so what's the deal? they are both new machines, re-formatted and installed in past couple days and the problems persist...
what is really bugging me is WHY they were assigned the same IP

anyone have any suggestions? i'm all out

 

[sswingle]

Are you SURE the DSL modem has a built in NAT router? I have seen DSL modems that had the router built in, but were hard coded to only give out one IP address, and had a subnet mask set so it could only talk to that single IP if you tried to manually set IPs. This was with Sprint DSL, but I'm sure that other DSL providers use similiar modems.

 

[Alex]

i'm fairly positive its a NAT router... it gives out a unique IP to 7 other computers here in the same workgroup and for some reason gives these two the same IP... is it a coincidence that they have the same mobo, etc?

 

[cleverhandle]

Is there a setting for the maximum number of DHCP leases in the router? If it's set for 8 leases, you already have 7 boxes, and then bring up 2 more, it may do funny things with that final lease.

 

[sswingle]

Ok, I didn't know you had 7 other computers. Although it shouldn't be possible, maybe they have the same MAC address?
Something to try, go into your routers setup page and see if you can manually assign computers IP addresses. Like on my Dlink, I get a list of computers that are on the network by name, MAC, and IP. Those are all dynamic. But I can click on an individual computer and tell it to always give a certain IP to a certain MAC. You could try assigning the two computers in question permanent IPs.
Also like cleverhandle suggested, its possible your router is set to only give out so many IPs.

 

[skyking]

Theoretically, there should be no duplicate MAC addresses. It could still happen.
Check the mac addy's of both computers and see.
Open a command prompt and > ipconfig /all
It will be listed as the physical address.
If they happened to be the same, change one of them in /local area connection-properties-configure-advanced-locally administered address

 

[Alex]

Originally posted by: skyking
Theoretically, there should be no duplicate MAC addresses. It could still happen.
Check the mac addy's of both computers and see.
Open a command prompt and > ipconfig /all
It will be listed as the physical address.
If they happened to be the same, change one of them in /local area connection-properties-configure-advanced-locally administered address

hmm awesome tip thanks! i never thought to look at the MAC addresses...
i actually get the rest of the week off so i'll have to check this out on monday!

as far as going into the router config page, its a lil more complicated cause the router is built into the DSL modem and typing the default gateway into a web browser doesn't work is there another way to do this that i'm not aware of?

 

[skyking]

Let me guess, sprint/earthlink DSL?

If so, they shipped out units that are telnet only. I have several of the default sprint passwords arround here somewhere

 

[cleverhandle]

Originally posted by: franguinho
as far as going into the router config page, its a lil more complicated cause the router is built into the DSL modem and typing the default gateway into a web browser doesn't work is there another way to do this that i'm not aware of?

Strange. Usually just browsing to the gateway works on any kind of router, built-in or not. Perhaps it's disabled for some reason. You could try telnetting - that often works too, and may give you a lot more config options than the web interface does. Failing that, there's probably an RS-232 serial console hookup (for normal consumer units) or a rollover RJ-45 (for Cisco, maybe others) on the back of the router.

 

[NordicNINE]

Originally posted by: skyking
Let me guess, sprint/earthlink DSL?

If so, they shipped out units that are telnet only. I have several of the default sprint passwords arround here somewhere

No, most of the Sprint/Earthlink boxes that have come out in the last year or two DO have a web interface.

 

[skyking]

not the two I just configured as bridges at my employer's business. they were telnet-only beasts.

 

[Alex]

i forgot to mention i live in brazil so its not any provider you guys would have heard of!

anyway i'll try telnetting into it and also checking the MAC address on monday!

 

[skyking]

In that case, have a good weekend.

 

[nweaver]

if you set them to DHCP, ipconfig /all will also show your DHCP server (it's IP address). If you are having problems, ipconfig /all from both machines would be very helpfull

 

[Alex]

UPDATED! SOLVED!!!

wooohoooO!

skyking i owe you a beer dude! :beer:

the MAC address thing worked... i had to google it and use some registry method cause what you said didn't exactly work but the idea was still friggin awesome! man i can't believe it all works now, what a beauty!

 

[skyking]

No hay por donde, man. glad to help.

<inside joke for spanish speakers, maybe you know some espanol along with the portuguese>