Intermittent SQL Server does not exist or access denied.

ASP.NET application with intermittent returns of 503 errors with the
following message.
System.Data.SqlClient.SqlException: SQL Server does not exist or access
denied. SQL Server does not exist or access denied.
An unhandled exception was generated during the execution of the
current web request. Information regarding the origin and location of
the exception can be identified using the exception stack trace below.
Servers running Windows 2003 SQL 2000.
This has been a problem for a long time (less than .3% of the time). No
code changes have been made. The only changes was Windows SP1 and post
SP patches on all servers. The patching may have made this issue more
pronounced.
Any suggestions from the experts?
Thanks,
RoxanneWhen they are intermittent they are difficult to track down.
Often those related to network connectivity issues. Have you
checked the event logs on the IIS box - particularly looking
for any network related issues?
-Sue
On 2 Nov 2005 10:32:52 -0800, roxy636@.yahoo.com wrote:

>ASP.NET application with intermittent returns of 503 errors with the
>following message.
>System.Data.SqlClient.SqlException: SQL Server does not exist or access
>denied. SQL Server does not exist or access denied.
>An unhandled exception was generated during the execution of the
>current web request. Information regarding the origin and location of
>the exception can be identified using the exception stack trace below.
>Servers running Windows 2003 SQL 2000.
>This has been a problem for a long time (less than .3% of the time). No
>code changes have been made. The only changes was Windows SP1 and post
>SP patches on all servers. The patching may have made this issue more
>pronounced.
>Any suggestions from the experts?
>Thanks,
>Roxanne|||Search no further...
http://support.microsoft.com/defaul...kb;en-us;328476
Note, this answer took forever to find so I'm posting everywhere...|||So was your solution to enable connection pooling? Or was it simply a
tcp/ip configuration issue. Unless you explicitly disable connection
pooling, then connections should be pooled, were you disabling pooling?
Thanks for any info, we are seeing the exact same symptoms at a client
of ours.|||Connection pooling was disabled for security reasons, so you need to
add registry keys specified in article here:
path:
HKEY_LOCAL_MACHINE\System\CurrentControl
Set\services\Tcpip\Parameters
type: DWORD
name: TcpTimedWaitDelay
value: 30 (decimal)
type: DWORD
name: MaxUserPort
value: 10000 (decimal)
Ultimately is connection ooliing is enabled this shouldn't happen, but
try it anyway. Check netsats from command prompt...if you see around
4000 connections in TIME_WAIT, then that is the problem.|||Thanks, since connection pooling is enabled and this is occuring even
soon after a reboot under low load. I do not suspect we are creating
too many connections to sql, but I do suspect some network
communication problems. I am going to further diagnose thier network
configuration relative to the front and back planes of the web server.
But I will not overlook this as a possibility, so I will also get a
netstat -n Thanks so much for the info..|||Turned out to be Bandwidth Throttling, disabling that option for the
Application Pool alleviated the HTTP 503 errors.