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"Slow network connection detected"

We ordered a NT4 Server and (of course) it was backordered, we then installed a demo (NFR) version of NT Server and everything worked fine untill the day we installed our "real" Server software, when we did this we got the following problems:

When we logon to our NT4(SP3) Server from a NT4 WS we get the message: "Slow network connection detected, would you like to download your profile or use your localy stored?" (That´s because we got our profiles stored on the server).
The problem is: Why is the network connection slow?

After downloading your profile you can work but file transferes seems a little bit slower than before.

If you try to map a shared folder on the server from a Win 3.11 machine you will find out that sometimes you can access the files without problems and the next time you can´t see them at all. They shows up in periods...

These are the things I´ve tried to solve the problem:

1. I used a 1 meter cable between the server and a workstation (with no other computers involved), just to see if the problem was caused by a cable length problem.

2. I´ve replaced all the hardware.

3. Right now we have two NIC´s installed in the server, I have tried with just one.

4. I´ve removed all protocools and added one by one.

5. I´ve reinstalled NT two times, even from scratch.

Here´s some information about our server:

Pentium 133 Mhz
96 MB RAM
One 2.1 GB and two 4 GB all SCSI-Wide
Adaptec 2940
Two 3ComIII Combo ISA
ATI Graphic adapter

I would be very greatful if someone could solve our major problem. We have tried for about two weeks now.

Sincerely

Christian Johansson
Consat Engineering AB

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zeedjej

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Edited text of question
The slow connection thing has to do with a connection accross  a phone line.  Usually you see this using RAS.  It disables the browser and uses cached profiles in an attempt to minimize traffic across the phone line.

You didn't mention if you have RAS installed and activated.  If you do, there is a setting to tell NT to use the slow connection when logging in, but I really don't remember it being available when using a NIC.

I doubt this is the answer you need, but if I were on your end, I'd poke around a bit and see if I could find a setting to change.
Your configuration should work.
Silly question: You did terminate the cable, do you?
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I don´t have RAS installed or avtivated. There is a "low connection" option in server manager but that one is not checked.

I did terminate the cable on both sides and I have tried with several different cables.

I discovered a strange thing this morning. When you look at connected users in server manager you will find out  that every user shows up two or even three times in the list.
Last thing is normal (I hope). One user has different connections to the server.
Did you checked network speed? Copy a large file and stop the time and/or use NT's systemmonitor.
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I have now done the test you told me to do, one interesting point is that the result is not the same when you copy from server --> workstation and from workstation --> server.

I did the test with a 15 MB file, here is the results:

Server to Workstation = 16 sec = 0.94 MB/s

Workstation to Server = 23 sec = 0.65 MB/s

???
For ethernet 1MB/s is the theoretical maximum. Your 0.94 is incredible fast, 0.65 seems OK. Maybe it is due to caching.

Seems your network connection is NOT slow. Question is why NT thinks it is slow. I do not know.

Just a comment, 1MB/s is not the maximum, I have reached 1.2 millions of bytes/sec on an Ethernet network.
Hey guys!

NT's version of a low speed connection has NOTHING to do with the speed of the transfer!

It only determines whether the browser is enabled or not.  See the RAS documentation.  I KNOW  YOU DO NOT HAVE RAS INSTALLED!  Look at the help files anyway!
NT's version of a low speed connection has to do with the speed of the transfer. I got low speed connections all the time when I was using a bad power supply for my hub, and since I fixed that, I've had no more low speed connections, with no changes in software.
Both maybe true. A real low speed connection will be detected and NT then does something to reduce traffic (i.e. disable the browser). Other task now look for this service and report a low speed connection whenever it is disabled.

y96anhha: 1.2MB/s ? It is a 10MBit network, I do not believe it is possible. Maybe this is due to a write cache.

zeedjej: Is your Browser running? See ControlPanel/services
cer: It's possible, remember, this is not an rs-232 line, you don't need 10 bits to transfer a byte. 1.2 * 8 makes 9.6, which makes this 96% efficiency. You can't get 100% because of the network addresses and such needing to be transferred.
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Sorry about the delay, The browser is running and works fine.
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Adjusted points to 250
Check out the actual settings of the 3-Com card and run the diagnostic utilities for the card.  You can obtain this program from the 3-com site for the E-link III series for free.

I have the 3c509b and use the 3c5x9cfg.exe utility to set up the cards.  If you are using Tp (twisted pair) check to see if you have full-duplex enabeld.  Is your network capable of full-duplex.  All cards should be set the same way when they are located on the same physical segment.

Matthew
I found some registry settings in the help files included with the resource kit.

I don't know if these will help, don't know if you've looked at them.

There are two settings: "SlowLinkDetectEnabled" and "SlowLinkTimeOut"

The text indicate that you can use the System Policy Editor to change both.

If you don't have access to the resource kit, let me know and I'll copy the text of these two settings for you.

And, yea!  I found out I was wrong.  Would you believe this is the first time it ever happened?
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All 3Com settings ar ok. By the way, everything worked fine until we upgraded our NT Server so there has been no changes to the NIC settings.  
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bartholis - I do not have access to the resource kit but the settings you mentioned sounds very interesting so I would be very greatful if you could copy the text section for me.
SlowLinkDetectEnabled    REG_DWORD
Range: 0 (disabled) or 1 (enabled)
Default: 1
Determines whether Slow Link Detection is enabled.  If the value of this entry is 1 (enabled), users can choose between local or server-based profiles when the value of SlowLinkTimeOut is exceeded.  The time alloted to users to choose between the local and server-based profiles is determined by ProfileDlgTimeOut
Note:  You can use the System Policy Editor to change this value.

SlowLinkTimeOut    REG_DWORD
Range: Milliseconds  0 - 120,000
Default: 2000 (2 seconds)
Sets a threshold for slow links to server-based roaming profiles.  If access to a server-based profile exceeds this threshold, and SlowLinkDetectEnabled is set to 1, users can logon by using a local profile instead ofthe roaming profile.
Note: You can use the System Policy Editor to change this value.

So, there you have it.  It doesn't seem to say anything about changing the connection, only disabling the detection.  Hope it helps.
barthollis: can you please give the full path to this key?
What happens if I disable slowlink detection? Can I use this to disable the use of the local profile?

HKLM\SOFTWARE
   \Microsoft
        \Windows NT
               \CurrentVersion
                     \WinLogon

I'm not sure.  I tend to think that it would force use of the server-based profile.  Unfortunately <G>, my system works well and I don't know how to trash it to duplicate the problem!

Tyr it.  Let us all know.
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barthollis: Thanks for the information!

 If I set SlowLinkTimeOut to 4s instead of 2s I don´t get the "slow conn..." message but unfortunily this is just a way to go around the problem and disable the error message. We still got some Win 3.11 clients and they don´t work correct.

We are about to upgrade all our stations to NT4 and if there is no other solution maybe I can live with it, but most of all I want to know why the connection is slow.
Uh huh.  That's about what I figured.  It just put's a patch over the problem so you don't see it but does not fix it.

Let's step back a little.  You said the "Demo" version worked OK, right?  Then you installed the "real" version and everything quit working OK, right?  I would think that means the hardware is all good and would quit looking there.  

You also said you did a "clean" install.  Does that mean you actually formatted the disk?  Is it too late to do that again?  I'd try doing a low level format using the program on the Adaptec controller and reinstalling, real slow and careful, to see if that worked.  I *hate* that answer, but sometimes it works.  

Have you considered a small amount of Plastique?<G>
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Hi Barthollis!

I´ve tried with 3 different disks, all new.

Today when I installed NT4 WS on a new Workstation and created a new computer account on the server I didn´t get the error  message on that workstation.

Maybe NT has lost the SID (Security Identifier) for each computer during the upgrade and maybe that´s why the connection seems slow.

I have tried to remove all computer accounts from Server Manager and then add them again but it won´t help. Only if I reinstall NT on the workstations and check the "create computer account" option during the setup.

It seems like we are close to a solution but maybe there is an easier way than reinstalling NT on every single workstation.
You can NOT change the SID of the computer, only the "Network SID" by rejoining the Domain.
Is it possible that the computers in question were installed by cloning (using Ghost or similiar) which makes identical installations with identical SID's ?

More Information about cloning:

The SID (Security Identifier) on a NT Workstation, on a NT Member Server, and on a PDC is generated during the GUI phase of
setup. The SID is used on the local machine, in conjunction with a RID to assign a unique ID to user accounts on that machine..
The Sid of a BDC is taken from the PDC as they share a common account database.

When a Workstation joins a domain. it is given a Domain SID by the PDC which is the PDC SID plus a unique RID. The
Workstation also remembers the domain SID.

In Windows NT 4.0 (and earlier), the PDC does not make use of the Workstations SID. There is a high probability that this will
change in the future.

So, can I clone my Workstation or Member Server? Yes, if you do it before the GUI phase of setup. If you do it after the SID has
been established, you are tempting the fates.

For more detail, see KB article Q162001

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"When a Workstation joins a domain. it is given a Domain SID by the PDC which is the PDC SID plus a unique RID. The Workstation also remembers the domain SID."

If I understand this correct this means that when I made a new install of NT  server on a new disk, the server was given a new domain SID.  And as you said, the workstations remeber the domain SID. That means that the workstations first "looking" for a Domain with the SID  xx but the server now got the SID yy.  I don´t think I got this rigtht.

If I´m wrong, could you please explain this for me in a more simple way.
You got this right. If you reinstall the PDC (fresh disk) the workstations cannot login there without rejoining the domain.
Otherwise you have a security problem. In your case it works because (maybe) the guest account is used? What does the eventlog say?

I think the SID's are the problem. I remember someone telling me that it is best to join a domain at installation time of the WS. Joining later will give difficulties.
You can remove/join a computer from/to a domain by using the servermanager (on the server) and as administrator while logged into the WS. Did you tried both ways ?

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Hi

The guest account is disabled and the event log says nothing (no errors reported).

I have now tried both way on our stations and actually I succeed on one station, on the other stations the problem still resist.


Strange. I can not offer more help, sorry.
For our installations I choosed a method where I can easyly fast and without error (fully automated) set up a WS (with all Apps). So in my case I would reinstall all WS, in your case .... ?

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I have know deleted all profiles for the user on one of our workstions, the local and the profile stored on the server. This did help on that machine but not on the other machines.

I consider to reinstall NT on those workstation that don´t work after the procedure above.

I leave the question open for I while to see if someone maybe get some other ideas.

Thanks to everybody who has been involved in my question!!!
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Hello everybody!...

I have reinstalled NT on our workstations and everything seems to work fine.

I see Experts-exchange as a knowledgebase and it would be stupid to delete this question. There´s been a lot of good advices and maybe some of them could help someone with the same problem.

Unfortunily I can´t split the points soo I decided to give them to "cer". His comments has helped me very much.

cer: If you see this, please post an answer to the question.
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