Internet goes on and off at the PCs of my work place.

The network there works with a domain server.

They use a combinations of hubs and routers to connect with each other,
some of them with windows 2000, some with XP, the server is 2000.

The problem is that a couple of days ago Internet service started to go
off on all the PCs of the network, then it would go back on.
This continued for a couple of days, until I contacted the ISP, blaming
them from the problem.
They said there are OK, so the problem is ours.
What could it be? I know very little of networking, any help greatly
appreciated.

In news:(E-Mail Removed) oups.com,
Starriol <(E-Mail Removed)> stated, which I commented on below:
> The network there works with a domain server.
>
> They use a combinations of hubs and routers to connect with each
> other, some of them with windows 2000, some with XP, the server is
> 2000.
>
> The problem is that a couple of days ago Internet service started to
> go off on all the PCs of the network, then it would go back on.
> This continued for a couple of days, until I contacted the ISP,
> blaming them from the problem.
> They said there are OK, so the problem is ours.
> What could it be? I know very little of networking, any help greatly
> appreciated.

When you say the internet goes (or turns?) off, does that mean browsing no
longer works because you cannot resolve any internet names such as
www.microsoft.com? Is this on workstations, servers or on ALL machines? Does
it happen to all machines all at once or just selectively?

When this occurs, can you ping by IP address from an affected machine? NExt
time this happens, try to ping 4.2.2.2 and see if you get an answer.

If the ping works, then it tells me, assuming Active Directory is involved,
that your workstations, maybe not be configured with ONLY the internal DNS
server and the DNS server either may have a Root zone created and/or
forwarders may not be configured properly or the forwarder is no longer
working.

Can you post an ipconfig /all from a workstation and from one of your DCs to
get a clearer picture of your infrastructure's configuration just to rule
out some of the basic things?

Thanks,

--
Ace

This posting is provided "AS-IS" with no warranties or guarantees and
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If you are having difficulty in reading or finding responses to your post,
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account, pointing to news.microsoft.com. This is a direct link into the
Microsoft Public Newsgroups, and it is FREE and DOES NOT require a Usenet
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Not sure how? It's easy:
How to Configure OEx for Internet News
http://support.microsoft.com/?id=171164

Ace Fekay, MCSE 2003 & 2000, MCSA 2003 & 2000, MCSE+I, MCT, MVP
Microsoft MVP - Windows Server Directory Services
Microsoft Certified Trainer
Assimilation Imminent. Resistance is Futile.
Infinite Diversities in Infinite Combinations.
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