Could use some help from a Smart Person(TM) <grin>

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G

Guest

Hi,

I'm struggling with a problem and was hoping that someone on this group
could point me in the right direction. I'm not looking for a free ride, just
a suggestion as to how best to use all the tools at my disposal to diagnose
the situation.

I have an existing COM+ / ASP application (the COM+ objects are written in
VB 6.0) that I am wanting to migrate forward to .NET (using VB.Net). I have
added some ASPX pages to the existing application that do relatively simple
things such as display lists of data from a SQL Server database, etc. I have
successfully deployed the application in a 5 server "Microsoft Load
Balancing" cluster (the application is designed to be stateless, so this
works very well).

Everything was fine until I got uppity and decided to add some code that put
up entry fields, dropdowns, etc. to allow users to change data in the system.
Everything tests out just fine on my Windows XP SP2 development machine but
when I deploy the application to the production environment, it randomly
locks up the entire .NET subsystem. I can still go to other web pages on the
server that use COM+ but any ASPX page just hangs when I try to click on it.

I added a table to the database that allows me to record where I'm at in the
application (i.e. a glorified printf function) that gets fancy and uses
reflection to capture a stack trace at each step along the way and it appears
to be hanging in a different place each time.

I'm pretty sure it is hung instead of looping because the CPU utilization on
the machine stays pretty much at zero and the memory consumed by the w3svc
process apppears to be nearly static.

The servers are IBM HS20 blade servers configured using IBM's "server
manager" installation disk. They all have the right version of the .NET
framework on them, they are running Server 2003 Standard Edition, and are
patched up to latest & greatest on everything but DirectX (never bother to
install the update but I would think it wouldn't matter).

Now for my questions:

1. Is there some way I can see where the thing is hung?
2. What recommendations can I get from the group on diagnosing the problem?
3. Is there anything special I need to do from an installation perspective
outside of creating the "application" thingy in IIS Manager (right click on
the directory where the application lives and tell it to create a new
application taking the defaults)

Thanks in advance,
Bryan
 
One question do you have other servers, other than blades, that it runs on?
I am facing a wierd problem on three new servers (blade) where out .NET
software does not work, errors, hangs, quits, sorta like yours! Is the the
blades fault? Don't know, is there software differences with our code NO, OS
yes?
 
Hi,

In Bryan's case, it could be "almost anything" that's causing the
problem. I've been running ASP.NET for over three years on a perfect
config Windows 2000 server with RAID1 boot and RAID5 data, and not a
single hang (except due to a developer error a few months back). Bryan's
app sounds like a mess to me - you don't use VB6 and VB.NET for COM, but
that may not be the problem. First thing I'd try is write a new test app
that does not use COM and see if that hangs too? If the new app crashes,
you know it's ASP.NET. If it does not crash, you know it's the COM stuff.

Actually, this raises an interesting point which is that .NET may simply
be too risky to run mission critical apps. The ability to track down
these types of errors does not exist in .NET, but it's a no brainer in
C++/COM.

In the case of Jim's servers, the first thing I'd check is whether non
..NET apps are also crashing, or is it only .NET stuff? He doesn't say
what o/s he's running or any other tech info; have all the server
management logs been checked and have all the event logs been checked?
What kind of test apps have been created to track down the problem?
 
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