Losing connection to outside DNS servers

I'm seeing an odd problem: 5 PCs within the 20-PC company keep losing their
connection to the Internet through the router. Without warning, they will
not be able to talk to the DNS servers of their broadband provider. They
still have full access to the server, and they can still ping every PC
within the organization, including the internal IP of the router itself.
The only way to get the access back is to reboot the PC. Through some
experimentation, it appears to me that the problem may actually rotate
between these PCs... in other words, when one PC is rebooted to restore
connection, one of the other five then loses connection.

I'm suspicious of the provider's router, even though they claim that
everything checks out. However, I want to make sure that something else
might not be the root of the issue. Windows Server 2003 licenses are tight;
we often get the message about approaching the limits of our licensing.
However, all of the PCs are set with static IP (no duplicates) and gateway,
and the gateway is the router itself, meaning that the Internet traffic
doesn't move through the server at all. Could this still be the cause of
the problem? Is there something else I should look at beyond the router?

Do you run DNS on your win 2003 server, and use Broadband providers DNS as
forwarders, and all cleints
use win 2003 DNS as primary server?
IF yes is win 2003 behind a firewall?

If no, then all clients use primary DNS as one of the
boradband provider DNS and also secondary DNS, etc.
as other DNS of boradband provider?

Also how does the client obtain IP address? is it through router DHCP,
or win 2003 DHCP, or static?

Is it that you use static pool from the ISP and the available pull is only
24, (one used by router, one used by server, and two used by leased line
modems, so you are left with only 20 IP for actual client usage.)

Sharad

"Ben Scaithe" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> I'm seeing an odd problem: 5 PCs within the 20-PC company keep losing
their
> connection to the Internet through the router. Without warning, they will
> not be able to talk to the DNS servers of their broadband provider. They
> still have full access to the server, and they can still ping every PC
> within the organization, including the internal IP of the router itself.
> The only way to get the access back is to reboot the PC. Through some
> experimentation, it appears to me that the problem may actually rotate
> between these PCs... in other words, when one PC is rebooted to restore
> connection, one of the other five then loses connection.
>
> I'm suspicious of the provider's router, even though they claim that
> everything checks out. However, I want to make sure that something else
> might not be the root of the issue. Windows Server 2003 licenses are
tight;
> we often get the message about approaching the limits of our licensing.
> However, all of the PCs are set with static IP (no duplicates) and
gateway,
> and the gateway is the router itself, meaning that the Internet traffic
> doesn't move through the server at all. Could this still be the cause of
> the problem? Is there something else I should look at beyond the router?
>
>

Sorry my last para in the previous reply is messed up since I was thinking
of something else, leased line modems do not use IP for themselves. Please
read the last para as below:

"Is it that you use static pool from the ISP and the available pull is only
16 IPs , (one used by router) so you are left with only 15 static pool IPs ?
In such case it will happen that if you reboot a client it will obtain an IP
from the static pool, while the router will disconnect one which has max.
idle time out of the 15.

Sharad

"Ben Scaithe" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> I'm seeing an odd problem: 5 PCs within the 20-PC company keep losing
their
> connection to the Internet through the router. Without warning, they will
> not be able to talk to the DNS servers of their broadband provider. They
> still have full access to the server, and they can still ping every PC
> within the organization, including the internal IP of the router itself.
> The only way to get the access back is to reboot the PC. Through some
> experimentation, it appears to me that the problem may actually rotate
> between these PCs... in other words, when one PC is rebooted to restore
> connection, one of the other five then loses connection.
>
> I'm suspicious of the provider's router, even though they claim that
> everything checks out. However, I want to make sure that something else
> might not be the root of the issue. Windows Server 2003 licenses are
tight;
> we often get the message about approaching the limits of our licensing.
> However, all of the PCs are set with static IP (no duplicates) and
gateway,
> and the gateway is the router itself, meaning that the Internet traffic
> doesn't move through the server at all. Could this still be the cause of
> the problem? Is there something else I should look at beyond the router?
>
>

We are using static IPs, meaning that the IP addressing, gateway, DNS info,
etc. is permanently configured on each workstation, and does not pull from
any DHCP source. We use our own internal IP address scheme, and don't have
any static pool from the provider limiting us. I have tried changing the IP
addresses of the affected machines, but the problem does not go away.

There has never been a problem with Internet access until a couple of months
ago. About that time, the router died and was replaced by the provider, so
my strongest suspicions are with that, even though they claim it's not their
problem. But just before that, we replaced our server with a Windows 2003
Server and upgraded many of the workstations from NT4 to Windows XP Pro
(excluding stations already on Windows 2000). So my other concerns are with
any other potential problems that would cause workstations to lose
connection with the external DNS servers.



"sharad" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Sorry my last para in the previous reply is messed up since I was thinking
> of something else, leased line modems do not use IP for themselves. Please
> read the last para as below:
>
> "Is it that you use static pool from the ISP and the available pull is
only
> 16 IPs , (one used by router) so you are left with only 15 static pool IPs
?
> In such case it will happen that if you reboot a client it will obtain an
IP
> from the static pool, while the router will disconnect one which has max.
> idle time out of the 15.
>
> Sharad
>
> "Ben Scaithe" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
> > I'm seeing an odd problem: 5 PCs within the 20-PC company keep losing
> their
> > connection to the Internet through the router. Without warning, they
will
> > not be able to talk to the DNS servers of their broadband provider.
They
> > still have full access to the server, and they can still ping every PC
> > within the organization, including the internal IP of the router itself.
> > The only way to get the access back is to reboot the PC. Through some
> > experimentation, it appears to me that the problem may actually rotate
> > between these PCs... in other words, when one PC is rebooted to restore
> > connection, one of the other five then loses connection.
> >
> > I'm suspicious of the provider's router, even though they claim that
> > everything checks out. However, I want to make sure that something else
> > might not be the root of the issue. Windows Server 2003 licenses are
> tight;
> > we often get the message about approaching the limits of our licensing.
> > However, all of the PCs are set with static IP (no duplicates) and
> gateway,
> > and the gateway is the router itself, meaning that the Internet traffic
> > doesn't move through the server at all. Could this still be the cause
of
> > the problem? Is there something else I should look at beyond the
router?
> >
> >
>
>

You didn't answer Sharad's question about your DNS setup. Are your
clients set up to use your local DNS server? Does your local DNS server
forward to your ISP DNS server?

Because NT used Netbios extensively, it was common to use Netbios names
locally and set the local clients to use the DNS at the ISP. This is not a
good scheme with a W2k/W2k3 domain. Your local machines should use your
local DNS, and it should forward requests for external name resolution.

"Ben Scaithe" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> We are using static IPs, meaning that the IP addressing, gateway, DNS
info,
> etc. is permanently configured on each workstation, and does not pull from
> any DHCP source. We use our own internal IP address scheme, and don't
have
> any static pool from the provider limiting us. I have tried changing the
IP
> addresses of the affected machines, but the problem does not go away.
>
> There has never been a problem with Internet access until a couple of
months
> ago. About that time, the router died and was replaced by the provider,
so
> my strongest suspicions are with that, even though they claim it's not
their
> problem. But just before that, we replaced our server with a Windows 2003
> Server and upgraded many of the workstations from NT4 to Windows XP Pro
> (excluding stations already on Windows 2000). So my other concerns are
with
> any other potential problems that would cause workstations to lose
> connection with the external DNS servers.
>
>
>
> "sharad" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
> > Sorry my last para in the previous reply is messed up since I was
thinking
> > of something else, leased line modems do not use IP for themselves.
Please
> > read the last para as below:
> >
> > "Is it that you use static pool from the ISP and the available pull is
> only
> > 16 IPs , (one used by router) so you are left with only 15 static pool
IPs
> ?
> > In such case it will happen that if you reboot a client it will obtain
an
> IP
> > from the static pool, while the router will disconnect one which has
max.
> > idle time out of the 15.
> >
> > Sharad
> >
> > "Ben Scaithe" <(E-Mail Removed)> wrote in message
> > news:(E-Mail Removed)...
> > > I'm seeing an odd problem: 5 PCs within the 20-PC company keep losing
> > their
> > > connection to the Internet through the router. Without warning, they
> will
> > > not be able to talk to the DNS servers of their broadband provider.
> They
> > > still have full access to the server, and they can still ping every PC
> > > within the organization, including the internal IP of the router
itself.
> > > The only way to get the access back is to reboot the PC. Through some
> > > experimentation, it appears to me that the problem may actually rotate
> > > between these PCs... in other words, when one PC is rebooted to
restore
> > > connection, one of the other five then loses connection.
> > >
> > > I'm suspicious of the provider's router, even though they claim that
> > > everything checks out. However, I want to make sure that something
else
> > > might not be the root of the issue. Windows Server 2003 licenses are
> > tight;
> > > we often get the message about approaching the limits of our
licensing.
> > > However, all of the PCs are set with static IP (no duplicates) and
> > gateway,
> > > and the gateway is the router itself, meaning that the Internet
traffic
> > > doesn't move through the server at all. Could this still be the cause
> of
> > > the problem? Is there something else I should look at beyond the
> router?
> > >
> > >
> >
> >
>
>