Comcast broadband, router: only one PC at a time

Are you using a straight through cable or a crossover cable ? Did you try re-booting the PC ? It should pick right up on any of the ports.

Reply to
$Bill
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Just got married and moved in with my wife, who has Comcast cable broadband. (Had previously been on Verizon DSL.) She has a Motorola SB1500 SURFboard cable modem and a LINKSYS BEFSR41 router; runs Windows XP Home. (Pretty sure it's SP2.)

Looking at the quick setup guide for the router, I tried plugging my Windows XP Home SP2 box in. Didn't work. Tried a few things, then finally got it to work when I found that I can get one computer (but not both) running broadband. Pattern seems to be that the one I plug into port 1 (or whatever it's called) on the router works, but not the other.

Any suggestions on how I can get both to work simultaneously? I did some web/USENET searches on this, and can't quite figure it out. (I went to the admin web page for the router, and it says it's set up for 50 PCs, not merely 1.)

TIA,

S
Reply to
Morris Ebbets

A couple of things. The cable modem should be plugged into the "WAN" port and port 1 is connected internally, but with reversed directional sense, to the "Uplink" port

If the router has DHCP enabled, you should configure your computers to seek a DHCP IP assignment from IP address 192.168.1.1. If DHCP is not enabled, manually assign the computers IP addresses in the range

192.168.1.[1..254]

You should also specify the router's address (192.168.1.1) as the DNS server.

Reply to
Tom Stiller

Yep! I fumble-fingered that one.

Well, my old BEFSR41 captures the ISP (Comcast) supplied DNS addresses. All the computers on my local network have manually assigned IP addresses and specify 192.168.1.1 as their DNS entry. I have no problem resolving URLs on any of them.

Reply to
Tom Stiller

Right you are.

I'm pretty sure it's not a configuration issue, because my XP box works when hooked up to port 1, and I'm pretty sure that it's running DHCP.

OK. Did all that.

Don't think it's the cable since P 1 works, but not 2-4.

Good idea. That's my leading hypothesis right now.

Forgot to do that...see my response to the entire thread for the info I

*did* gather.

Reply to
Morris Ebbets

Straight.

I've cycled a number of times. Works on Port 1 but not 2-4.

Reply to
Morris Ebbets

Thanks, all, for the kind and informative replies.

As I mentioned in some of my comments to specific replies, I tried it again, this time only hooking up my XP box and not my wife's. (I was careful to power everything off, then power the modem on, let it stabilize, then power the router on, and then the PC, for each cycle.)

Things work fine when I'm connected to Port 1; they don't work when connected to ports 2, 3, or 4.

One odd thing: on ports 2-4, while I can't download web pages, it seems I can ping out, e.g. yahoo. The tracert to yahoo on e.g. port 4 was pretty much the same as that on port 1 (though not quite the same; not sure if that's because yahoo sends you to different IP addresses on a random basis...for port 1 it went to [216.109.112.135], for port 4, to [66.94.234.13]).

The output of ipconfig /all was the same for all four ports (except for the specifics of the DHCP lease). Here it is for port 1: Windows IP Configuration Host Name . . . . . . . . . . . . : apollo Primary Dns Suffix . . . . . . . : Node Type . . . . . . . . . . . . : Unknown IP Routing Enabled. . . . . . . . : No WINS Proxy Enabled. . . . . . . . : No DNS Suffix Search List. . . . . . : hsd1.md.comcast.net. Ethernet adapter Local Area Connection 2: Connection-specific DNS Suffix . : hsd1.md.comcast.net. Description . . . . . . . . . . . : NETGEAR FA311 Fast Ethernet Adapter Physical Address. . . . . . . . . : 00-02-E3-24-AC-B3 Dhcp Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes IP Address. . . . . . . . . . . . : 192.168.1.100 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.1.1 DHCP Server . . . . . . . . . . . : 192.168.1.1 DNS Servers . . . . . . . . . . . : 68.87.64.196 68.87.66.196 68.48.0.13 Lease Obtained. . . . . . . . . . : Tuesday, October 04, 2005

2:26:09 PM Lease Expires . . . . . . . . . . : Wednesday, October 05, 2005 2:26:09 PM

At this point my best guess is that which one of you suggested, namely, a bad router...

Any further thoughts?

Thanks again,

S
Reply to
Morris Ebbets

I ran multiple pc's using that same router before I upgraded to wireless. I didn't have to do anything except make sure the router and all pc's were configured for DHCP. You might want to do a reset of the router to get it back to factory settings in case osmething has been changed. Then just make sure it's set for DHCP. Check the pc's for DHCP too.

Reply to
Dave

You're welcome. I know I've made my share of mistakes and that's the primary reason why I like public newsgroups and open source software; there are always sharp-eyed observers to see that the emperor is fully clothed ;-)

Reply to
Tom Stiller

Before replacing the router, you might download and install the latest firmware from the support page at

Reply to
Tom Stiller

The cable modem is probably a SB5100, I hope. :)

Not much to go on here, but the basics are that the router's Internet port, sort of off to one side by itself, should be connected to the cable modem, and the PC(s) should be connected to any of the ports labeled 1-4. The PC(s) should be configured for DHCP, (easiest to get working; you can do static IP assignment outside of the router's DHCP range later.) Power down the cable modem, the router, and the PC(s), then power up the cable modem and let it stabilize, power up the router and let it stabilize, then power up one PC at a time. Make sure there are Link lights at both ends of all live (powered up) cables. Rule out a bad patch cable. If Port 1 works on the router, but 2-4 don't, you may have a bad router. If you have all of the necessary Link lights, see if you can ping the LAN side of the router from the 'bad' PC, (usually at 192.168.1.1), and if that works, ping the cable modem, (usually at 192.168.100.1). The ping results will help you determine where to go next.

Reply to
Bill M.

I don't think the BEFSR41 has that relationship between Port 1 and the WAN (Internet) port, and there is no "Uplink" port. Some older equipment was like that, though.

Eek! 192.168.1.1 is already in use by the router's LAN port, so your example for the computers should be 192.168.1.[2..254].

Sorry to be nit picky, I'm just trying to avoid confusion.

Reply to
Bill M.

From: "Tom Stiller"

| A couple of things. The cable modem should be plugged into the "WAN" | port and port 1 is connected internally, but with reversed directional | sense, to the "Uplink" port | | If the router has DHCP enabled, you should configure your computers to | seek a DHCP IP assignment from IP address 192.168.1.1. If DHCP is not | enabled, manually assign the computers IP addresses in the range | 192.168.1.[1..254] | | You should also specify the router's address (192.168.1.1) as the DNS | server. | | -- | Tom Stiller | | PGP fingerprint = 5108 DDB2 9761 EDE5 E7E3 | 7BDA 71ED 6496 99C0 C7CF

You mean the range is; 192.168.1.2 ~ 192.168.1.254 ( 192.168.1.[2..254] )

191.168.1.1 is reserved by the Router.

The Linksys BEFSR41 does not have DNS Daemon and thus 191.168.1.1 should not be entered into the DNS settings of the platform. That should be manually entered based upon what the Comcast segment provides or better yet, Enable DHCP on the platform such that it gets the complete stack, including the Comcast DNS servers, via DHCP.

Reply to
David H. Lipman

From: "Tom Stiller"

| | Well, my old BEFSR41 captures the ISP (Comcast) supplied DNS addresses. | All the computers on my local network have manually assigned IP | addresses and specify 192.168.1.1 as their DNS entry. I have no problem | resolving URLs on any of them. | | -- | Tom Stiller | | PGP fingerprint = 5108 DDB2 9761 EDE5 E7E3 | 7BDA 71ED 6496 99C0 C7CF

Well Tom I tested it on my BEFSR81 and you are correct ! That is news to me and I have installed too many BEFSR41 (Model v1, v2 and v3) to keep track of ;-)

Thanx for the correction.

Mea culpa !

Reply to
David H. Lipman

I just checked my own router to see if it had the option to disable certain ports in the QoS config, but it only allows ports to be set at a High or Low priority. I don't see anything about completely disabling them, and I assume yours is the same. Even so, as has been suggested, it probably wouldn't hurt to do a full reset to put everything back to factory defaults. Either stick a paper clip into the reset hole or reset it via the Admin page.

So far, it was sounding like ports 2-4 are dead, but you said ping works through each of them, so they aren't dead after all. *shrug*

Reply to
Bill M.

I just got Comcast broadband and they gave me an RCA DCM315. It is working fine but am I missing something? Should I be asking for another model?

Thanks,

Bob

Reply to
Hymer

No. My cable modem is at least a couple years old. The reason it's "new" for me is that I got married, so I cancelled my DSL and tried to hook my machine up to my wife's router.

Reply to
Morris Ebbets

[snip]

I tried both reseting the router with a paper clip, as well as upgrading to the latest firmware. No joy.

Bought a wired/wireless router this am...

Reply to
Morris Ebbets

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