VB DCOM issue

[CasperTFG]

Hello all,

I have an issue with a DCOM installation at a customer site. The product runs across 2 servers A client application can start the Systems on the server using DCOM authentication.

The problem I am having is this. The systems will be up and running for several days and then all of a sudden they stop responding and the error
[tt]
Automation error
The server process could not be started because the configured identity is incorrect. Check the username and password.
[/tt]
is returned.

At first I thought that the customer changed the users password, and therefore caused the issue. However it happened again a few days later.

I need to get the the root of the problem but don't even know where to start. Any thoughts.

Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".

 

[dilettante]

Here is one article that might be related:

http://support.microsoft.com/kb/q276407/

 

[CasperTFG]

Doesn't really help,

The user is set up correctly because the program was running for 3 weeks. The user and rights are correct. I am trying to find an explanation as to why it will all of a sudden loose memory of it's user rights?

Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".

 

[avanderlaan]

Casper,

I believe your problem is in the DCOM config on the server(s). However, your explanation of the system architecture is not complete enough to diagnose the problem. Can you provide more info? For example, what does "runs across 2 servers" mean? Where are the client applications located?

 

[CasperTFG]

Hi avanderlaan,

The application is written almost entirely in VB with COM+ / DCOM. The main protion of the application consists of a COM+ Server and a COM+ Library. There are subsequent server applications.

These are DCOM servers that can be distributed across several servers, to perform the actual work of the program. For instance there is one server that reads an external database. One that accepts TCP/IP connections, Another that allows for live streaming of data, etc. In total there are 16 of these DCOM Servers that perform various things.

These server processes can all be run on one machine or on as many as 16 machines depending on how large a system is needed.

In this particular instance, the servers are split between 2 Servers. A client application is able to connect in to these servers to view data and remotely run the system.

The security settings are set up as follows.
1) The COM+ Server is set to run as "This User:" COMPANY_DOMAIN\AppUser
2) The DCOM Servers are set up to run as "This User:" COMPANY_DOMAIN\AppUser

The COMPANY_DOMAIN\AppUser is a local administrator on each of the servers as well as a local administrator on each Client PC.

What is happening is that the application will be running fine. Then all of a sudden it stops responding, Server machine A is unable to see or connect to the running DCOM servers on the other machine and vice versa. The COM+ is still fine, it is only the DCOM where the error returned is this.

DCOM got error "The server process could not be started because the configured identity is incorrect. Check the username and password. " from the computer SERVER_B when attempting to activate the server:
{30493AFB-5F17-4908-8EE4-BB6E4A8BB3A3}

Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".

 

[avanderlaan]

You need to go into DCOMCnfg on each physical machine and set the RUN AS user and password for each DCOM server class on that machine. You must also look at the authentication required by each class.

Also, just WHERE is the error reported? By a client trying to instantiate a class, etc.?

 

[CasperTFG]

Hi avanderlaan,

The security is set up for each DCOM server on each Machine. Here are the values entered for each Entry. Oh this is Windows 2000 Server SP4 on each of the servers.

General
Application name: CCMNTSUBSYS.MntSubSysMgr
Application type: local server
Authentication Level: Default
Local path: C:\Program ... etc.

Location
Run application on this computer

Security (DOMAIN\AppUser is contained in the custom of each)
Use custom access permissions
Use custom launch permissions
Use custom configuration permissions

Identity
This User
User: DOMAIN\AppUser
Password: *****

The error is Reported on Machine_A when calling to Machine_B.

e.g.
A call is made in from a Client PC to connect to the subsystems. All Calls are directed through Machine_A, so the call from the client goes to Machine_A, to connect to a subsystem. Machine_A sees that the server process should be run on Machine_B, so it calls to Machine_B and is responded back with the error about Login Credentials.



Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".

 

[avanderlaan]

Verify that Domain\AppUser has access & launch/execute permissions for each component on machine B.

 

[CasperTFG]

Done that... he does...

The program has has been working since August of last year. Just all of a sudden for some reason, they rebooted the machine and it stopped working. Everything resonded with the user credentials error. They looked in DCOM and all the entries were there, I ahd them re-run the script that sets the security credentials and it came back up again.

I only need to find out why? oh why? it happened in the first place.

Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".

 

[avanderlaan]

Is DOMAIN\AppUser an admin on each of the servers(local) or in the domain? Your error indicates that the user does not have permission to launch the application.

What is "resonded"? Your permissions have changed between reboots for either the user or machine between reboots.

 

[CasperTFG]

Hello avanderlaan,

yes the user is a local administrator on each server and on each client PC.

Sorry that should have said "responded".

Here is the exact Error from the event log.

DCOM got error "The server process could not be started because the configured identity is incorrect. Check the username and password. " from the computer CONCENTER5 when attempting to activate the server:
{30493AFB-5F17-4908-8EE4-BB6E4A8BB3A3}

I am thinking that either the user got screwed up, or somehow DCOM forgot who was allowed to run this.

It is a real tough place because I need to prove that this is a windows problem and not a problem with my software, but if I can't get to the root of the problem then there is always a question of was it windows or the app.

Thanks for your help.

Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".

 

[avanderlaan]

I think you should reconfigure the Run AS user+password for EVERY DCOM server class. Be sure the user should be domain\user.

 

[CasperTFG]

That is how I corrected it the first time it happened, but then it happened again.

Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".

 

[avanderlaan]

Are they expiring passwords? Are they using password synch in the domain?

 

[CasperTFG]

I asked them about expiring passwords, they tell me no, but it is hard to beleive. I also asked them if they had done anything like reboot the machine. They told me no, but from the Event logs I see that they did!!!

I will ask about the "Password Synch" in the domain. Could you point me to any information on this so that I know what to ask them.

Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".

 

[avanderlaan]

Not really, I am about helped out here.

 

[CasperTFG]

I am going to set the problem with the client to pending re-occurance... Hopefully it will not happen again. Thanks for all the suggestions.

Casper

There is room for all of gods creatures, "Right Beside the Mashed Potatoes".