Received a very descriptive ticket this morning. It read
Short Description: 2 computers are not able to access the SQL Server
Ticket Summary: There are 2 computers that are trying to access the SQL Server – OGDBvm
IP addresses of computers are: 10.0.4.24, 10.0.4.23.
When trying to connect to the SQL server, they receive the error – attached.
If a SQL user “maple,” uses the odbc connection from computer 10.0.4.22 – it can connect successfully.
If the SQL user “maple,” tries to connect from the computers 10.0.4.24 and 10.0.4.23 – they receive and error – see attached.
We have had the network team verify that there is nothing blocking the connection. Can you check the server to see if connections are allowed from these systems.
This issue originally started happening on 1/27/2017 – ticket. INC0891787.
This is a critical application for the department and currently they can only access it from one computer.
ODBC & Netstat
On client computer, accessed ODBC Control Panel applet and tried connecting to Data Source.
On another window on same machine, launched DOS Command Shell and issued netstat -an | find “SYN_SENT”.
Immediately confirmed that we are seeing noticed SYN_SENT on port 1433 targeting DB Server.
Query Analyzer ( ISQLW)
It is a SQL Server 2000 Server and so issued isqlw and even had problems connecting locally.
Server: Msg 17, Level 16, State 1, Line 0
[Microsoft] [ODBC SQL Server Driver] [TCP/IP Sockets] SQL Server does not exist or access denied.
Server: Msg 10061, Level 16, State 1, Line 0
[Microsoft] [ODBC SQL Server Driver] [TCP/IP Sockets] ConnectionOpen (Connect()).
Using Task manager noticed High Memory Consumption by SQL Server Process.
Stop DB Server hoping it is just a runway DB Engine, but no not that easy.
SQL Server – Error Log
Reviewed SQL Server Error Log
Image – Listening On
SQL server listening on Shared Memory, Named Pipes.
Confirmed that we listening on Shared Memory and Named Pipes.
But, I do really need to be listening on TCP/IP.
SQL Server Network Configuration
Launch SQL Server Network Configuration and confirmed that TCP is enabled and it is listening on SQL Server Default TCP Port of 1433.
TCP/IP – Port – 1433
TCP/IP – Port – 50000
Temporarily changed to another port, 50000, that I know is not being used
SQL Server Restarted
Restarted SQL Server so that the new TCP/IP can be effectual, but still not listening on TCP.
Confirmed by issuing “netstat -anb“. Noticed our SQL Server Port is not one of the Listening Ports.
When bac to Control Panel and accessed Networking and TCP/IP Protocol.
Ensured that TCP/IP Filtering is not enabled.
Took to the net to determine what can cause SQL Server not to listen on its assigned TCP-Port.
Now thinking back to yester years, or is Wonder years, before Blaster Worm.
And, all the havoc that occurred that Friday night.
Validate Current Version
Connect to box insisting on np and ran “select @@version“.
Microsoft SQL Server 2000 – 8.00.194 ( Intel X86)
SQL Server 2000 Version Matrix
Here is the Version Matrix for SQL Server 2000
Mapping Our Version # ( 8.00.194 ) to the matrix confirms that we are running SQL Server 200 Release To Manufacturing ( RTM).
Download SQL Server 2000 SP4
The fix of course is to download Microsoft SQL Server 2000 SP4.
SQL Server Error Log
Launched SQL Server Enterprise Manager and reviewed error log
SQL Server Error Log – Listening On
SQL server listening on TCP, Shared Memory, Named Pipes.
Dedicated to the Network Firewall Team
Our Network Firewall guy says that even he were to run monitoring all day, the problem is still occurring at the Application Layer.
He continued that he is seeing traffic originate from the client workstation, but the Server is rejecting the request right away.
And, that the server is not even listening in on the port we are targeting.
The moral of the story is that when a Network Engineer is offering you a bet, don’t take it. Go do your homework.