users loosing access

[Ralph Shumway]

My network is simple:

A netware 3.x box, now all the data is on a Win2k server with Netware
installed. So the Netware box does authentication, the Win2000 server
holds the sysvol folder and data.

Now for the LAN. There was two 10based T hubs which I replaced. Now
there is a 16 port switch (SMC)leading to all the workstations and the
server. From there one port leads to a LANNET Repeater running
thinnet coax to the Novell box. There is also a port going to the SMC
4 port gateway which has a WAN port running to the DSL Bridge.

Last week I installed LANSuite software which is an all IP based
mail/web/proxy server. Before I replaced the hubs I moved some cables
from the hub to the gateway (it has 4 ports and they are 10/100,
right?). All of a sudden. people are complaing of being "kicked out"
of the apps that access the data on the 2000 server. The data is
being offered by Netware File and Print Services. I watched one
station where Peachtree was hanging and I opened explore to the Novell
drive and all of a sudden Peachtree came back to life.

What is causing this problem or more importantly, how can I isolate
it?

As I sit here I am getting a good view of the thinnet repeater and at
times it lights up like a christmas tree.

Any suggestions?

 

[Andy Konecny]

As I sit here I am getting a good view of the thinnet repeater and at
times it lights up like a christmas tree.

Sounds very much like you likely have a physical layer problem. One
issue could be that the wiring isn't quite up to 100Mbs, so forcing the
workstations to 10Mbs might stabilize things nicely. Also take a good
look at all your connections as loose connector can cause all kinds of
problems. A rule of thumb, don't go cheap on the cable and
installation as trouble shooting them can be a very painful process.

Its a pity none of your platforms have much in the way of port
statistics available. NetWare didn't get much until 4.x, Windows
really hasn't gotten any, so seeing what line level errors will require
getting a real protocol analyzer into the equation to see what is
actually happening on the wire.


Andy Konecny
Ainsworth Inc. Toronto, Canada
[are you following the Directory Enabled Net Infrastructure Model]
The real action for Novell peer support, see
http://support.novell.com/forums/

 

[Ralph Shumway]

Thanks for the reply Andy. I came in this morning to "very slow"
network and immediately forced the systems on autonegotiate to 10mps.
Do you recommend full or half duplex?

I am awaitingto see where we go from here.

Send me an email directly if you don't mind so I can thank you
"off-group".

Ralph Shumway
(e-mail address removed)

 

[Ralph Shumway]

Its a pity none of your platforms have much in the way of port

statistics available. NetWare didn't get much until 4.x, Windows
really hasn't gotten any, so seeing what line level errors will require
getting a real protocol analyzer into the equation to see what is
actually happening on the wire.

OK.

I've installed Etherscan Analyzer. Whhich packet types will help me
see problems such as we have discussed here? How do I see line level
errors?

 

[Kevin D. Snodgrass]

Thanks for the reply Andy. I came in this morning to "very slow"
network and immediately forced the systems on autonegotiate to 10mps.

I haven't used anything Microsoft for quite some time, but
the MS drivers used to have major problems with
autonegotiate. Force the wire speed and frame type, i.e.
Ethernet or Fast Ethernet; 802.2 or 802.3.

Do you recommend full or half duplex?

Full duplex requires a switch port or router since
collisions are not detected. Reading your original it looks
like you have a switch, so that shouldn't be an issue.

 

[Barry OGrady]

Sounds very much like you likely have a physical layer problem. One
issue could be that the wiring isn't quite up to 100Mbs, so forcing the
workstations to 10Mbs might stabilize things nicely.

I don't think coax (thin ethernet) is capable of 100 Mbs.

Also take a good
look at all your connections as loose connector can cause all kinds of
problems.

Can a loose connector cause loose access?

A rule of thumb, don't go cheap on the cable and
installation as trouble shooting them can be a very painful process.

He should change to twisted pair.

Its a pity none of your platforms have much in the way of port
statistics available. NetWare didn't get much until 4.x, Windows
really hasn't gotten any, so seeing what line level errors will require
getting a real protocol analyzer into the equation to see what is
actually happening on the wire.


Andy Konecny
Ainsworth Inc. Toronto, Canada
[are you following the Directory Enabled Net Infrastructure Model]
The real action for Novell peer support, see
http://support.novell.com/forums/

-Barry
========
Web page: http://members.optusnet.com.au/~barry.og
Atheist, radio scanner, LIPD information.
Voicemail/fax number +14136227640

 

[Andy Konecny]

MS drivers used to have major problems with
autonegotiate. Force the frame type, i.e.
802.2 or 802.3.

Yes, this certainly is a known issue as well and your recent changes
could have triggered this problem. I've had to do this once over a
700+ PC network, but at that level you do registry edits from the login
script, sounds like you have few enough that it is easiest to do
manually. Just make sure it matches what is on the NetWare server
which is most likely 802.3. If both are present, 802.2 is the
preferred, but usually not an issue sufficient to go through switching
over to it.


Andy Konecny
Ainsworth Inc. Toronto, Canada
[are you following the Directory Enabled Net Infrastructure Model]
The real action for Novell peer support, see
http://support.novell.com/forums/

 

[Andy Konecny]

Full duplex requires a switch port or router since
collisions are not detected. Reading your original it looks
like you have a switch, so that shouldn't be an issue.

Ideally yes, but as seen before, autonegotiate has been a known
problem even at this level even though not as bad a problem as speed
and frame type negotiation.


Andy Konecny
Ainsworth Inc. Toronto, Canada
[are you following the Directory Enabled Net Infrastructure Model]
The real action for Novell peer support, see
http://support.novell.com/forums/

 

[Andy Konecny]

I've installed Etherscan Analyzer. Whhich packet types will help me
see problems such as we have discussed here? How do I see line level
errors?

The trick is that you need a NIC that doesn't autofilter out bad or
damaged packets. I'm not sure which NICs qualify for that any more as
the environments I work in gather that level of issues at the Cisco
Switches, leaving a clean playing field for looking at application
layer issues. I know that 3Com was one of the first NIC manufactures
that built such normally very useful features into their products, so
recommendation is to use the cheaper & older NICs for such testing.
Etherscan isn't one I've used so I can't help you with it.

Good luck.


Andy Konecny
Ainsworth Inc. Toronto, Canada
[are you following the Directory Enabled Net Infrastructure Model]
The real action for Novell peer support, see
http://support.novell.com/forums/

 

[Andy Konecny]

I came in this morning to "very slow"
network and immediately forced the systems on autonegotiate to 10mps.
Do you recommend full or half duplex?

So did that help at all?
Half duplex is the safer of the two, especially for troubleshooting,
but the important thing is that both ends of the connection are the
same, so if into a hub it should be halfduplex at the client, if into
a switch then make sure the switch port is set to the same as the
client.

For direct contact, we want NOSPAM taken out of the already posted
address. For future reference, you don't want to post a real address in
a newsgroup as the spammers do harvest from here as I have found out
when I missed spamproofing it as it is now.


Andy Konecny
Ainsworth Inc. Toronto, Canada
[are you following the Directory Enabled Net Infrastructure Model]
The real action for Novell peer support, see
http://support.novell.com/forums/

 

[Ralph Shumway]

Ok, one and all, here it is.

When I first showed up to this sight I added an SMC Barricade 7004VBR
Gatewate/Router inbetween the network and their DSL connection. I
removed it and the problem vanished. Go figure...

Anythoughts or comments?

I've installed Etherscan Analyzer. Whhich packet types will help me
see problems such as we have discussed here? How do I see line level
errors?

The trick is that you need a NIC that doesn't autofilter out bad or
damaged packets. I'm not sure which NICs qualify for that any more as
the environments I work in gather that level of issues at the Cisco
Switches, leaving a clean playing field for looking at application
layer issues. I know that 3Com was one of the first NIC manufactures
that built such normally very useful features into their products, so
recommendation is to use the cheaper & older NICs for such testing.
Etherscan isn't one I've used so I can't help you with it.

Good luck.


Andy Konecny
Ainsworth Inc. Toronto, Canada
[are you following the Directory Enabled Net Infrastructure Model]
The real action for Novell peer support, see
http://support.novell.com/forums/