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Maximum concurrent connections in use error

Posted on 1997-10-23
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Last Modified: 2008-03-06
Hi.

We have 1200 users there 800 is students. The amount of logins and logouts is very high. Every now and then some, different users every time, of the users get the message "Maximum concurrent connections in use" but they are not logged in. We must have the setting "Maximum connection = 1".
I have tried to change the settings for the "watchdog" but this problem remains.
Why? How do I solve this problem?

Thanks

Mikael Hellberg
0
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Question by:Mikael012197
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11 Comments
 
LVL 4

Expert Comment

by:saar2
ID: 1590919
This is happens because the users don't use the logout command - they just turn-off the computer.

It takes time for the server to see that a workstation is inactive and the ping it a few time to check if it is connected to the network.

Only after the server is sure the phisical connection to the workstation is lost it clears the logical connection (which you can see in the Console Monitor).

You can ask the server to send less Watchdog before it understand that the connection is lost.
You also can ask the server to send Watchdogs more often, but this may make the network speed slower because there will be much more traffic.

(This configuration can be done by the Servman NLM or by the SPXCONFG.NLM which can be downloaded from Novell's site.)

But after all it will take the server a few minutes to clear the connection.

We have the same problem in our school. What we do is nothing!
After few times the students learn to make logout before they close the computer - becuase they want to login again... (every user has free Internet connection - you can understand by yourself :-))


Saar
saar@bigfoot.com
0
 

Expert Comment

by:stotter
ID: 1590920
There is a nice little NLM called NLICLEAR.NLM that comes with Netware 3.11 or up.

(NLICLEAR = Not Logged In Clear)

You can set it to poll the net and clear unused connections every nn seconds.
0
 

Author Comment

by:Mikael012197
ID: 1590921
Hi Saar.

I´m sorry, but some of the users try in the morning and can´t get in. Then they try in the evening and still can´t get in.

To Stotter: I´ll try it.

Mikael
0
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LVL 4

Expert Comment

by:saar2
ID: 1590922
which netware version are you using?

Try to check in the console monitor is they are logged in when they can't login to the network. If the monitor says that they are logged in, it means that your server doesn't send watchdog packets.

Try to set the parameter Console Display Watchdog Logouts to be Yes and this way you'll be able to check it out.

Another problem could be with the SPX protocol - download&install the SPX kit from Novell's site.

------
Stotter - I think that NLICLEAR.NLM won't help because if the stations were marked as Not Logged In he whould have this problem.


0
 

Author Comment

by:Mikael012197
ID: 1590923
Hi Saar2.

No, our users is not marked as "Logged-in" when this happens. Our version is 4.11 with support pack 4 installed.
I´ll download the SPX-fix from Novell and try.
0
 
LVL 1

Expert Comment

by:lindr
ID: 1590924
Which version of the client are you using?
I had the same problem when using Client32 v2.12 but when I upgraded to v2.2 problem disappeared.
0
 
LVL 5

Expert Comment

by:jstegall
ID: 1590925
There are several things that can cause this, In Win95 the user can have a permanent connection or mapping to some other servers
volume and the logout doesn't log him out of the tree just one
server.  This happened more with the older Client32 now it happens if the machine the user cycles the machine and gets another connection number before the hung connection is cleared.
The server will see the new connection but still have the old connection and since they both have the same mac address it will not be cleared by Watchdog.  There is also NDS not getting updated so nds say he is logged in but doesn't show on console
connections. The cure for one case is the user can cycle the system until the client get the connection on the same port as the hang, then when he login the first will be cleared. One
other case is where a laptop user with a docking station fails to log out properly due to error or undocking his system.  since the dock with the NIC is still connected the watchdog will be answered so the user remains logged in so if an attempt is made to log in from a different workstation it will fail with the "Maximum concurrent connections in use" message.  Novell has a TID that covers a case where the NDS user object has a problem.
Do a search in file finder for remadr.exe. Its case sensative.
See below:


     Network Address in NDS Preventing User Login  (Last modified: 30SEP1997)

     This document (2913235) is provided subject to the disclaimer at the end of this document.
         Forward this document to a colleague
         Submit comment about this document to its author

     Symptom

     Sometimes a user object's Network Address property contains one or more network addresses
     (network:node:socket) when it should not. For example, even though a user is not logged in to
     the NDS tree, the user object still shows a value for the Network Address property. (A user's
     Network Address property can be viewed in NetAdmin or NWAdmin on the Environment page.)

     This can cause problems for users that have a limited number of concurrent connections. For
     example, when a user tries to login, LOGIN might return the following error:

     MESSAGE
     "LOGIN-4.12-830: You are trying to log in to too many stations simultaneously. The supervisor
     has limited the number of connections you may have."

     How can these "connections" be cleared out of DS when they don't appear in Monitor and
     NWAdmin does not have a "delete" option for the Network Address property?

     Cause

     The causes are two fold, both of which are being addressed.

     1) If the client workstation is not logged out properly, (just turned off, or rebooted), the network
     address property in the DS database does not get cleared out. When attempting to log back in,
     there is a good chance that the socket that is used will not be the same as what it was
     previously. Hence, when the entire address is check, that being NETWORKADDRESS - NODE
     ADDRESS - SOCKET, it fails the comparision of being the same network address according to
     DS and therefore will not allow login.

     2) DS detects the above condition and leaves the network address property for the user. An
     address in this type of scenario currently has no method of timing out.. Hence, the address
     sticks.

     Solution

     Prevention:

     This situation can be minimized by installing v5.06 (or later) of DS.NLM on every NetWare 4.10
     server and applying all of the latest NetWare OS patches on all servers. However, remember that
     it is both a client and server issue.

     Quick Fix:
     2 methods same results
     1) load dsrepair -N1 This clears for all users
     2)To clear out a user's Network Address property, a utility called REMADDR.EXE (currently in
     the download file In NSD area called REMADR.EXE) can be used. Syntax: REMADDR
     CN=USER1.NOVELL Refer to REMADR.TXT for more information.
     This clears one user at a time.
     Outstanding Issue:
     Even when the latest DS.NLM and the latest OS patches have been applied, there is still one way
     in which a value can become stuck in a user's Network Address property. If the server console
     command DISABLE LOGIN is used at a server and a user subsequently attempts to login, the
     user will be denied access, but the user's Network Address property will be updated with their
     network address. Novell is aware of this issue and is working on a solution.

     Search: 830 exceeded maximum limit logins allowed simultaneous users attribute node socket
     NDS DS

                    Please select if this document solved your problem.

      Document Title:
                          Network Address in NDS Preventing User Login
      Document ID:
                          2913235
      Creation Date:
                          11SEP96
      Modified Date:
                          30SEP97
      Document Revision:
                          7
      Novell Product Class:
                          NetWare OS
      Novell Product and Version:
                          NetWare 4.1


     DISCLAIMER

     The Origin of this information may be internal or external to Novell. Novell makes all reasonable efforts to verify this
     information. However, the information provided in this document is for your information only. Novell makes no
     explicit or implied claims to the validity of this information.

     Any trademarks referenced in this document are the property of their respective owners. Consult your product
     manuals for complete trademark information.
0
 
LVL 5

Expert Comment

by:jstegall
ID: 1590926
Have you looked at my previous comment?  I can submit that as an answer if you unlock the question.
0
 
LVL 5

Expert Comment

by:jstegall
ID: 1590927
Are you still around? Did my suggestion work? I have used the
REMADDR.EXE to clear ghost connections, it works, I have two
laptop user that have this problem often, They undock without telling Win95 to undock.
0
 

Author Comment

by:Mikael012197
ID: 1590928
Hi, everyone.
Yes jstegall, I´m still here.

Is this solution only working under Win95 or in DOS/Win3.11 also?
This problem is mostly with DOS/Win3.11 not with Win95. The client we are using is the one that followed with the CD (January 1997).
I´ll try your tip and get back as soon as possible!

Micke
0
 
LVL 5

Accepted Solution

by:
jstegall earned 200 total points
ID: 1590929
The solution is independant of the client you are using.  The problem happens more often in Win95 than DOS/WIN because of the way Win95 works, but any client can have the problem when not
properly logged out.  You must train your users to allways logout
before turning of the workstation or undocking a laptop, and
when they lock up in a program only turn the machine off as a last resort and inform you of any problems rebooting.  It has been months since I had to use REMADDR but I know it can happen again at any time.
In your situation I would create a batch file that would take
one parameter, the user you want cleared and have the helpdesk
user with the rights to make this change to all students.  Then when a student couldn't get on he/she could tell the monitor to clear his NDS connections.  If the user is truly logged in from a working workstation it will not be cleared but then a clear connection from console would clear that.  You can decide from a security standpoint how you want to handle this.
HTH
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