Internet Connection Sharing weirdness

[ariana_paris]

I have an XP machine and a Windows ME laptop. The XP machine is
connected to a USB broadband modem and configured as a host for ICS.
The ME laptop is the client. They are linked by a Netgear RP114 router
(both connected to LAN ports).

The two machines can ping each other and browse folders etc, but the
Internet sharing is bizarre. I can occasionally download emails from
various hosts using Outlook Express, but I mostly can't visit any web
sites ("The page cannot be displayed"... though I sometimes seem to be
able to load www.knittingforums.co.uk when nothing else is working,
even areas I would have said weren't cached!).

I'd suspect a cable problem or a dodgy connection, but it seems bizarre
that I can still connect to one web site (sometimes) and always
ping/browse the rest of the network if the physical connection was
down. Needless to say, the XP machine is always happily connected to
the Internet, and I even get an Internet Gateway icon on the laptop,
accurately telling me how long the ADSL connection has been up. Anyway,
I thought I'd see if anyone has a suggestion about this...

 

[Steve Winograd [MVP]]

I have an XP machine and a Windows ME laptop. The XP machine is
connected to a USB broadband modem and configured as a host for ICS.
The ME laptop is the client. They are linked by a Netgear RP114 router
(both connected to LAN ports).

The two machines can ping each other and browse folders etc, but the
Internet sharing is bizarre. I can occasionally download emails from
various hosts using Outlook Express, but I mostly can't visit any web
sites ("The page cannot be displayed"... though I sometimes seem to be
able to load www.knittingforums.co.uk when nothing else is working,
even areas I would have said weren't cached!).

I'd suspect a cable problem or a dodgy connection, but it seems bizarre
that I can still connect to one web site (sometimes) and always
ping/browse the rest of the network if the physical connection was
down. Needless to say, the XP machine is always happily connected to
the Internet, and I even get an Internet Gateway icon on the laptop,
accurately telling me how long the ADSL connection has been up. Anyway,
I thought I'd see if anyone has a suggestion about this...

This is a common problem with DSL connections that use PPPoE, but
usually only if the host computer is running the original version of
Windows XP (no service packs). For details, please see this Microsoft
Knowledge Base article:

Connectivity Problems on ICS Clients When You Use a PPPoE Connection
on a Windows XP ICS Host
http://support.microsoft.com/kb/319661/en-us

Note that in the recommended "ping" command:

ping -f -l MTU_size default_gateway_IP_address

the "-l" option is a minus sign followed by the lower case letter L.
For example, using the recommended starting MTU size of 1454 and a
hypothetical default gateway address of 123.123.123.123:

ping -f -l 1454 123.123.123.123
--
Best Wishes,
Steve Winograd, MS-MVP (Windows Networking)

Please post any reply as a follow-up message in the news group
for everyone to see. I'm sorry, but I don't answer questions
addressed directly to me in E-mail or news groups.

Microsoft Most Valuable Professional Program
http://mvp.support.microsoft.com

 

[ariana_paris]

This is a common problem with DSL connections that use PPPoE, but
usually only if the host computer is running the original version of
Windows XP (no service packs).

Thanks for your help so far. I did have a look at the article you
suggested, but the host is using XP Home with SP2, and the ADSL modem
is configured as a "dial-up" device (using PPPoA, apparently), so there
is no corresponding entry in the Network section of CurrentControlSet.
The ping test did fail at higher than 1470 on the laptop, but given
that the other conditions are different from the article, I'm not sure
how to proceed further along that route.

However, while composing this reply, I've made some minor progress. I
decided to fire up Outlook Express on the laptop, and it just
downloaded my email... but only from the accounts I'd just checked on
the XP machine. Further tests reveal that the laptop can indeed "find"
web sites I have visited on the host within the last minute or so.

Is it possible that the XP machine is temporarily caching DNS data for
sites I have visited there - and that this cache is the only DNS
information it makes available to the laptop? If so, any suggestions on
how to force the XP machine to forward requests to the external DNS
servers? I tried hard-coding them on the laptop, but that had
absolutely no effect.

 

[ariana_paris]

information it makes available to the laptop? If so, any suggestions on
how to force the XP machine to forward requests to the external DNS
servers? I tried hard-coding them on the laptop, but that had
absolutely no effect.

Of course, the answer to that last bit is "hard-code the external DNS
servers in the right *@!# place on the laptop" - doh! So, actually,
hard-coding the DNS servers worked, which makes a lot more sense.

I'll assume that the XP machine isn't forwarding the requests as all
the documentation suggests it should because of some setting somewhere
(it isn't my machine, so I have no idea what half the gizmos on it are
there for). Thanks for the help, anyway!