Intermittent error: SQL Server does not exist or access denied

I need some help. I've seen this error has randomly occured for many
people, but I still haven't found a solution that works. We have a new
web application that is load balanced between two new web servers,
which are located in a DMZ. This is the only website running on these
servers. It connects back to a SQL server which is located inside of
the network. The web servers are running Win2003 Server w/SP1, IIS 6.
The SQL Server is running Win2k Server / SQL 2000.
When logging into the site, it connects back to a database located on
the SQL server to retrieve login information. I'd say 90% of the time
it works fine, but other times when attempting login it will pause for
a few seconds and then eventually display the error "SQL Server Does
Not Exist or Access Denied." The stack trace is pointing back to the
database which contains the accounts. I've done quite a bit of
research on this and have already tried a few things. I've verified
that we are connecting via TCP/IP, and named pipes is blocked through
the firewall. I've also made these registry entries related to
connection pooling, which were suggested in the links below:
path:
HKEY_LOCAL_MACHINE\System\CurrentControl
Set\services\Tcpip\Parameters
type: DWORD
name: TcpTimedWaitDelay
value: 30 (decimal)
type: DWORD
name: MaxUserPort
value: 10000 (decimal)
5052" target="_blank">http://www.experts-exchange.com/Dat...530
5052
http://support.microsoft.com/?kbid=328476
Modifying the registry did not help, as the error still randomly pops
up. When running a netstat -n from the web servers, I do not see a
large amount of connections in the TIME_Wait state. As I said these are
load balanced web servers and we have generated the error after
connecting through each one at random times. There is no real pattern.
It can fail in one attempt, then I will try again a few seconds later
and it logs in just fine with no errors. I'm able to make succesful
test connections through ODBC and telnet from the web servers to the
SQL server. The database it is failing on is shared between other web
apps, but there does not appear to be a very high load when the errors
are occuring. If anyone has any other suggestions besides the ones
I've listed then I would love to hear them. This error seems to be
getting more and more common from the research I've done. If someone
is able to help me resolve this I will give you all the points I
possibly can!!
Please let me know if you need anymore info.To me that sounds like a network issue. I would try the basics,
changing network cables, switches, that sort of stuff.