faulty NIC?

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I have two w2k conected to a ADSL router (Vigor2600x)
One of the computers would not be pinged from another (request timed out)
but it can ping the other computers and the Rourter and it cennects to the
Internet and it connects to a remote corparate network via VPN - does this
mean that the NIC on that computer is OK and the fault is elsewhere?
 
I have two w2k conected to a ADSL router (Vigor2600x)
One of the computers would not be pinged from another (request timed out)
but it can ping the other computers and the Rourter and it cennects to the
Internet and it connects to a remote corparate network via VPN - does this
mean that the NIC on that computer is OK and the fault is elsewhere?
Click to expand...

It probably means that you need to have a look at your firewall.
 
- If it's a hardware firewall: Consult the manual
- If it's a software firewall (ZoneAlarm, Trend, McAfee,
Norton): temporarily disable the whole package. Check
the FAQs on the suppliers home page if necessary.
 
This is exactly what beats me.
I have not knowingly installed any software firewall on any of the two
computers.
The ADSL router (Vigor2600x) is said to have a built-in firewall.
The two computers are plugged symmetrically to the router. The only
assymmetry is that the IP address of one computer is mentioned in the Router
settinggs as "Start IP Address" - what is this?

In theses circumstances what might be wrong with the firewall settings on
the router that they affect one computer but does not affect the other?

The router sees the "wrong computer" - in the Ethernet ARP Cache Table it
shows the MAC Address of the other computer and it is the same as the
physical address returned on the other computer by ipconfig /all

The only difference in the two computer settings is that ipconfig /all on
the "wrong computer" returns
IP Routing Enabled:yes
and on the "right computer" it returns
IP Routing Enabled:no

But I cannot figure out where this setting is controlled from - do you know?
And is this relevant to my pinging problem?
 
You don't mention anything about your virus scanner. Many
of them come with an integrated firewall.
 
You're right, Pegasus. I have InoculateIT running, but I have it on both
computers and its settings are identical.
Although it has a five-tab parameter seting interface, the word "firewall"
is not mentioned.
What else should I look at?
 
I don't know Inoculate, and I do not know if it has a firewall.
Here is what I would do in this situation:
- Turn off Inoculate on all machines.
- Try a different network adapter.
- Try a different network cable.
- Set all adapters to 10 MBits/s half duplex for the duration
of the test.
- Start a Command Prompt, then run the command below
on one good and one bad PC, then post the output file
from each PC in this thread.

ipconfig /all > c:\ipconfig.txt
 
Thanks, Pegasus

1. I turned off Inoculate, I swapped the cables. I can't try a different
card as I do not have it.
How do I set an adapter to 10 MBits/s half duplex ?
I tried Device Manager but I could not find any facility to do this

2. On the "bad" computer Event Viewer there are a lot of errors
"The DHCP allocator has disabled itself on IP address 192.168.1.13, since
the IP address is outside the 192.168.0.0/255.255.255.0 scope from which
addresses are being allocated to DHCP clients. To enable the DHCP allocator
on this IP address, please change the scope to include the IP address, or
change the IP address to fall within the scope. "

Is this relevant?
I do not understand how this might happen as the system is set to obtain IP
addresses automatically
 
See below.


aa said:
Thanks, Pegasus

1. I turned off Inoculate, I swapped the cables. I can't try a different
card as I do not have it.
Click to expand...

Buy one. They are dirt cheap.

How do I set an adapter to 10 MBits/s half duplex ?
I tried Device Manager but I could not find any facility to do this
Click to expand...

Look at the properties for your network connection. One of the tabs
lets you examine the network adapter itself. There are usually
several further tabs, one of which talks about adapter speed and
mode.

2. On the "bad" computer Event Viewer there are a lot of errors
"The DHCP allocator has disabled itself on IP address 192.168.1.13, since
the IP address is outside the 192.168.0.0/255.255.255.0 scope from which
addresses are being allocated to DHCP clients. To enable the DHCP allocator
on this IP address, please change the scope to include the IP address, or
change the IP address to fall within the scope. "
Is this relevant?
Click to expand...

Don't use DHCP during testing - use your own addresses.
Your DHCP server appears to be on the 192.168.0 subnet, so make
your machines 192.168.0.10, 11 and 12, with a subnet mask of
255.255.255.0. Note that you might lose access to the Internet
during these tests.
I do not understand how this might happen as the system is set to obtain IP
addresses automatically
Click to expand...

You can't get an address automatically while you have underlying
problems with network connectivity.
 
1. Buy one. They are dirt cheap
I do not have a PC store in my village, so I have to order one over the
Internet.
Do you mean that the normal Internet connection via NIC, and ability to
connect to corporate network via Intenet, do not mean that NIC is OK?

2. There are usually several further tabs, one of which talks about adapter
speed and mode.

On the Local Area Connection propertiey I indeed have a button "Configure"
relating to the NIC.
It has four tabs: General, Advanced, Driver, Resources and none of them
containg any references to the speed.

3. Your DHCP server appears to be on the 192.168.0 subnet

But all my computers (includung the two which are working OK are assigned
192.168.1.x addresses. Is it OK if DHCP is on a different subnet then the
rest of the computers. Also the router, which inplements DHCP is
192.168.1.1 - is it OK that the DHCP is nevertheless on the 192.168.0 subnet
?
 
See below.


1. Buy one. They are dirt cheap
I do not have a PC store in my village, so I have to order one over the
Internet.
Do you mean that the normal Internet connection via NIC, and ability to
connect to corporate network via Intenet, do not mean that NIC is OK?
Click to expand...

It is extremely rare but I have seen one or two cases where a network
adapter rejected one particular IP address.

2. There are usually several further tabs, one of which talks about adapter
speed and mode.

On the Local Area Connection propertiey I indeed have a button "Configure"
relating to the NIC.
It has four tabs: General, Advanced, Driver, Resources and none of them
containg any references to the speed.
Click to expand...

Have another look ad "Advanced". It's right there.

3. Your DHCP server appears to be on the 192.168.0 subnet

But all my computers (includung the two which are working OK are assigned
192.168.1.x addresses. Is it OK if DHCP is on a different subnet then the
rest of the computers. Also the router, which inplements DHCP is
192.168.1.1 - is it OK that the DHCP is nevertheless on the 192.168.0 subnet
?
Click to expand...

No, it's not OK. Put your PCs on the same subnet as your DHCP
server (i.e. your router). You must beable to ping your router/DHCP server.
You can probably do without DHCP if you set your Default Gateway and
your DNS address to the same value as the router address (192.168.1.1).
 
1. Have another look ad "Advanced". It's right there.

Nope. I am on w2k Pro Sp4 and I have 11 properties listed there none having
obvious connection to the speed. Perhaps it is coumuflaged under a seemingly
irrelevant name?
Or may be my NIC (Xircom Cardbas Ethernet II 10/100) does not allow to set
speed?

2. No, it's not OK. Put your PCs on the same subnet as your DHCP server
(i.e. your router).
How do I do it if IP address is set to obtained automatically?
 
1. Have another look ad "Advanced". It's right there.

Nope. I am on w2k Pro Sp4 and I have 11 properties listed there none having
obvious connection to the speed. Perhaps it is coumuflaged under a seemingly
irrelevant name?
Or may be my NIC (Xircom Cardbas Ethernet II 10/100) does not allow to set
speed?
Click to expand...

I would be very surprised if it did not. What are the 11 properties?

2. No, it's not OK. Put your PCs on the same subnet as your DHCP server
(i.e. your router).
How do I do it if IP address is set to obtained automatically?
Click to expand...

Select the radio button "Use the following IP address" . . .
 
1. I was wrong - 11 properties are on the "good" PC. On the wrong one I have
just three:
delay time
media type
network adress (BTW, this is set to Not Present)

2. Select the radio button "Use the following IP address" . . .
This mean departing from automatic addresses to static addresses. I
appreciate this might solve the problem. However I am interested to
inderstand what is wrong with my automatic addresses and why I have
computers, router and the DHCP server on different subnets - any ideas?
 
1. I was wrong - 11 properties are on the "good" PC. On the wrong one I have
just three:
delay time
media type
network adress (BTW, this is set to Not Present)
Click to expand...

See what's there under "Media Type". Check every other
tab too if you cannot find it there.

2. Select the radio button "Use the following IP address" . . .
This mean departing from automatic addresses to static addresses. I
appreciate this might solve the problem. However I am interested to
inderstand what is wrong with my automatic addresses and why I have
computers, router and the DHCP server on different subnets - any ideas?
Click to expand...

It is very difficult to do trouble-shooting when things are on
automatic! Learn to walk first (i.e. do things manually), then
try to run (i.e. let DHCP do its job).
 
Thanks Pegasus.
Incedentally, I've just solved my original problem - timeout during pinging
which made me wondering is my NIC was OK
Actually you were right in your first post. The problem was in the firewall
but the firewall which was sitting in the VPN client (Lucent). My sysAdmin
when re-installing this client for some reason (or just accidentally) set it
to "Allow client initiated traffic" which in Lucent means prohibit anything
else. When I changed it to Allow all traffic (this is how the Admin set it
on the good computer) everything returned back to realtive normality. The
funniest thing is that SysAdmin has been sending me irrelevant advisies
including to re-install the whole system.

I will certainly take your advise about turning off DHCP. As a matter of
fact I was thinking about this earlier and even floated a thread "Obtaining
IP address automatically vs setting it manually?" but the unanimous verdict
was "let DHCP do its job"
 
The conclusion to this thread is a trifle annoying: In my first three
replies I recommended clearly and in detail for you to look at your
firewall. It seems you glossed over this advice and misdirected
the thread towards totally irrlevant networking issues, which you
were not well experienced to deal with. Still, I appreciate it that
you posted the ultimate cause of your problems.
 
"I recommended clearly and in detail for you to look at your
firewall. It seems you glossed over this advice and misdirected
the thread towards totally irrlevant networking issues, which you
were not well experienced to deal with"
Click to expand...

In my original message I mentioned using VPN and later I expressly asked you
where exactly I should look for firewall settings, and I do not recall you
mentioning VPN among possible source. Instead you suggested me to buy and
install a new NIC.
I indeed am not experienced in networking at all, but I have common sense
sufficient to tell me that if the PC can communicate with another network,
but cannot be pinged, replacing NIC is most probably irrelevant and
definitely time consuming, so I abandoned this idea till I try others more
relevant and less time consuming. Nevertheless I was thankful for your
attempts to help me.

Yet now you feel it possible to reprimind me publically.

Still, I appreciate it that you actually did a correct guess in your first
message, to which I returned after seeing that the subsequent messages were
leading nowhere.
Thanks
 
Respondends have extremely limited knowledge about
posters' PCs. They must often guess what the source
of the problem could be. In this thread, my initial guess,
repeated in three replies, was correct. When the dialogue
between the poster and the respondent works well, the
poster will run with the respondents guess and explore
it in detail, with the help of this detailed knowledge of his
machine. This did not happen here until very late.

About my suggestion to buy a new network adapter: I said
explicitly that it was extremely rare for a network adapter
to fail in this way. Since I was led to believe that my initial
guess was wrong, I had to explore other, far less likely
avenues.

You may be a little touchy about "being reprimanded". I would
consider it a learning exercise. There have been numerous
threads where I was proved wrong in newsgroups, inspite of
my expertise. I simply added those cases to my knowledge
and experience, and moved on.

And as I said in my previous reply: I appreciate you taking
the time to post the conclusion, instead of just letting it go.
This is helpful to me and to others who are likely to follow
this thread.
 
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