Need help with Modem + Switch + 4 PC's

bamacre

Lifer
Jul 1, 2004
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Here is the setup to keep it simple...

Cable modem (which can dish out 10 dynamic public IP's) is hooked up to my Zonet 8-port switch. There are four XP-based computers hooked directly up to that switch.

Now, I have had two systems running like this perfectly fine. I added a third PC, and it could not acquire an IP, so I called my ISP. They reset the cable modem from their end, and boom, got all 3 PC's with an IP. Cool, right?

Now, I am adding a fourth, and at first everything was cool for a small amount of time. However, the two new ones needed rebooting, and now, for the life of me, I cannot get all 4 PC's acquiring an IP address at the same time.

I tried rebooting the cable modem, and the switch, and everytime I do so, one of the four systems cannot acquire an IP. It's never the same system, either. This is driving me insane.

Anyone know what I could do here?
 

JackMDS

Elite Member
Super Moderator
Oct 25, 1999
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Since you are IPs are coming from the ISP, it time to call them again.

:sun:
 

bamacre

Lifer
Jul 1, 2004
21,029
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Originally posted by: JackMDS
Since you are IPs are coming from the ISP, it time to call them again.

:sun:

Yeah, I will tomorrow. It's just crazy, doesn't make sense at all. I have 3 up and running now, the 4th just refuses to acquire an IP from the modem.
 

JackMDS

Elite Member
Super Moderator
Oct 25, 1999
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Well you probably are aware that you are one of the very few that use external IPs for a LAN, Millions of people use Cable/DSL Routers.

:sun:

 

bamacre

Lifer
Jul 1, 2004
21,029
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Originally posted by: JackMDS
Well you probably are aware that you are one of the very few that use external IPs for a LAN, Millions of people use Cable/DSL Routers.

:sun:

Yes, I know it is a rather odd way of doing this, but I have a very specific reason for it. Four are just simple systems anyway, with zero important data on then. The other actually has a router between it and the switch acting as a hardware f/w.
 

kevnich2

Platinum Member
Apr 10, 2004
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This sounds like an IP issue with the cable modem and issuing that many public IP's. Although I agree with Jack on this, why would you use that many public IP's anyway. Just put a router on the modem and hook everything to the router, voila. Even in business environments, I only use public IP's when absolutely needed for server requirements (mail, ftp, http) server and even then, I only need one public IP and just forward the different ports of the public IP's to the different servers. Also, a switch is not a hardware firewall, it'll pass any data through that is sent to it.
 

bamacre

Lifer
Jul 1, 2004
21,029
2
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Originally posted by: kevnich2
This sounds like an IP issue with the cable modem and issuing that many public IP's. Although I agree with Jack on this, why would you use that many public IP's anyway. Just put a router on the modem and hook everything to the router, voila. Even in business environments, I only use public IP's when absolutely needed for server requirements (mail, ftp, http) server and even then, I only need one public IP and just forward the different ports of the public IP's to the different servers. Also, a switch is not a hardware firewall, it'll pass any data through that is sent to it.

Like, I said, I have a specific reason for needing multiple public ip's, actually for outgoing requests.

And the router is between my main system and the switch, so, my main rig has a local IP, as the router takes on one of the public IP's.
 

JackMDS

Elite Member
Super Moderator
Oct 25, 1999
29,553
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Yeah there is a special condition that some people need few external IPs (like buying in outlets auctions that would not allow the same IP to bid multiple time on multiple items etc.).

You need to work it out with your ISP I doubt that any one else can help you in this matter.

:sun:
 

bamacre

Lifer
Jul 1, 2004
21,029
2
81
Nah, I don't bid for items in auctions. I have purchased (BIN) a few things on ebay, but that has nothing to do with what I am doing here. And, no, I am not doing anything unethical.

Good News, however, just spoke with my account rep, and voiced a little concern because folks at Road Runner can't stay consistent with what they are telling me. He's sending out a guy to remove this cable modem, hook up a router, and they are giving me 5 static IP's for no additional charge. That's a big help to me since they will be static, and it will terminate this little buggy problem I am having.