Re: Laptop cannot connect

On Wed, 13 Jun 2012 05:24:16 +0000 (UTC), fred <frednot@hotmail.com>
wrote:

>neighbor has offered me a guest account on his wifi
>connection. He bought a linksys router, I think it's a t1200.
>Problem is when he powers down his main computer I am unable
>to connect to the net. Ping to the DHCP server is ok.
>Packetsto DNS servers go out but do not return on dns lookup.
>The account is set up for 5 guest accounts with password
>(which he has given me) and is unencrypted. ipconfig /all
>reports an assigned 192.168.xxx.xxx and to me and lease is ok
>and an assigned gateway IP, but no replies to dns lookups.
>The router is on a separate power connection, but when he
>leaves and powers off his computer, I can no longer
>connect-or so it seems. Neither of us has a clue as to what
>is causing the problem. Ping to dns servers, regardless if
>from ISP or public fail. Tried two different laptops both
>connecting fine until he left and turned off his box. When I
>told him about the problem on his return he
>powered back on and suddenly I can connect again. My signal
>strength on both laptops I tried is good. He is running win7
>and I am running either 98se or XP. He knows less than I do
>about this. I have not tried to access the router page as I
>do not have admin privileges and have wanted to check here
>first before asking neighbor to do anything with router
>settings. Any help appreciated.

Weird. Some rhetorical questions:

1. The router may be on a seperate power strip, but what about the
DSL or cable modem? Is that being powered off?

2. Did you power cycle the router AFTER the owners machine was turned
off to see if it magically recovers with his machine still turned off?

3. Is the owners machine connected via wired or wireless? If wires,
run IPCONFIG on his Win7 box and see if you get the usual
192.168.1.xxx or if you get a routeable IP address. If routeable, he
has the CAT5 cables miswired in back of the router.

4. Check the firmware version:
<http://homesupport.cisco.com/en-us/support/routers/E1200>
Note that v1 is quite different from v2.

5. If a DSL modem on the evil AT&T, is the PPPoE login in the DSL
modem, in the router, or in the owners Win7 machine? I prefer to have
it in the router, but it's much easier in the modem. It should not be
in the Win 7 machine. If the owners machine starts with "click here
to connect to internet" it's time to reconfigure.

6. What do the lights do on the router and modem when the owner
powers off his machine? I think there's an "internet" light on the
router that checks for connectivity. What does it do?

Looking at the settings, there's nothing on the guest page that might
cause problems.
<http://ui.linksys.com/files/E1200/2.0.00/guest_access.htm>

I would guess #1 as mostly likely.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 6/15/2012 8:53 AM, Jeff Liebermann wrote:
> On Wed, 13 Jun 2012 05:24:16 +0000 (UTC), fred<frednot@hotmail.com>
> wrote:
>
>> neighbor has offered me a guest account on his wifi
>> connection. He bought a linksys router, I think it's a t1200.
>> Problem is when he powers down his main computer I am unable
>> to connect to the net. Ping to the DHCP server is ok.
>> Packetsto DNS servers go out but do not return on dns lookup.
>> The account is set up for 5 guest accounts with password
>> (which he has given me) and is unencrypted. ipconfig /all
>> reports an assigned 192.168.xxx.xxx and to me and lease is ok
>> and an assigned gateway IP, but no replies to dns lookups.
>> The router is on a separate power connection, but when he
>> leaves and powers off his computer, I can no longer
>> connect-or so it seems. Neither of us has a clue as to what
>> is causing the problem. Ping to dns servers, regardless if
>>from ISP or public fail. Tried two different laptops both
>> connecting fine until he left and turned off his box. When I
>> told him about the problem on his return he
>> powered back on and suddenly I can connect again. My signal
>> strength on both laptops I tried is good. He is running win7
>> and I am running either 98se or XP. He knows less than I do
>> about this. I have not tried to access the router page as I
>> do not have admin privileges and have wanted to check here
>> first before asking neighbor to do anything with router
>> settings. Any help appreciated.
>
> Weird. Some rhetorical questions:
>
> 1. The router may be on a seperate power strip, but what about the
> DSL or cable modem? Is that being powered off?
>
> 2. Did you power cycle the router AFTER the owners machine was turned
> off to see if it magically recovers with his machine still turned off?
>
> 3. Is the owners machine connected via wired or wireless? If wires,
> run IPCONFIG on his Win7 box and see if you get the usual
> 192.168.1.xxx or if you get a routeable IP address. If routeable, he
> has the CAT5 cables miswired in back of the router.
>
> 4. Check the firmware version:
> <http://homesupport.cisco.com/en-us/support/routers/E1200>
> Note that v1 is quite different from v2.
>
> 5. If a DSL modem on the evil AT&T, is the PPPoE login in the DSL
> modem, in the router, or in the owners Win7 machine? I prefer to have
> it in the router, but it's much easier in the modem. It should not be
> in the Win 7 machine. If the owners machine starts with "click here
> to connect to internet" it's time to reconfigure.
>
> 6. What do the lights do on the router and modem when the owner
> powers off his machine? I think there's an "internet" light on the
> router that checks for connectivity. What does it do?
>
> Looking at the settings, there's nothing on the guest page that might
> cause problems.
> <http://ui.linksys.com/files/E1200/2.0.00/guest_access.htm>
>
> I would guess #1 as mostly likely.
>
FWIW, I put the settings in the router. The 2wire DSL modem should
detect you have connected a router. It turns off its firewall, expecting
the router to do that.

I'm not on AT&T, but I bought one of their 2wire routers since they are
very good. [I don't use it as a router or for wireless. I just use it
for the modem.] Yeah, I know, the wall wart sucks. Thus far, mind hasn't
failed, and I never have to boot the modem. I occasionally have to boot
the linksys router to get the wifi working.

:)

On Sun, 17 Jun 2012 00:48:58 +0000 (UTC), fred <frednot@hotmail.com>
wrote:

>My best guess is the router is not clearing stale connections
>unless you disconnect and clear them prior?

If that's the case, it might be the MAC address to IP address table
(ARP cache), or the DHCP leases that are not getting cleared on
disconnect. The ARP cache usually defaults to about 4 hrs. The DHCP
leases might be set to several days. No clue if these are the correct
timings for the E1200. I couldn't find settings in the E1200 router
setup to change either of these.
<http://ui.linksys.com/files/E1200/2.0.00/>
However, if my guess(tm) is correct, you should have had no trouble
reconnecting to the router. Both the ARP cache and DHCP lease tables
should have had your previous connection info and allowed a DHCP lease
renewal, if your computer requests a DHCP renewal, instead of a new IP
address. If it asks for a new IP address, then a DHCP lease table
will prevent any additional IP addresses from being allocated.
Cranking up the maximum number of connection to 10 will help, but
eventually it will run out of IP's.

Check for firmware updates for the E1200. It might have been fixed.
However, I couldn't find anything specific in the release notes for
either V1 or V2.

Put an electronic timer on the power to the router and have it do a
power cycle in the middle of the night. That should clear everything.
I use those for rebooting unreliable router on mountain tops.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS