Shulou(Shulou.com)05/31 Report--

What this article shares to you is about the troubleshooting methods that SQL Server does not exist or refuse to visit. The editor thinks it is very practical, so I share it with you to learn. I hope you can get something after reading this article.

1 the raising of the question

When a new client fails to connect to the database server (install SQL Server 2000) and says "[DBNETLIB] [ConnectionOpen (connect ()).] SQL Server does not exist or refuse access", the system cannot log in and the other clients are working normally.

2 solving process and train of thought

For this kind of fault prompt, the solution to this fault described in the general information is to check the settings of the firewall and port 1433 on the client. The malfunctioning client is equipped with Kaspersky 6.0Internet Security Suite. After adding port 1433 to Kaspersky's "Network Settings", the fault prompt becomes "General Network error (recv ())". There are many reasons for this kind of fault message, which is not easy to determine. To this end, comparing the SQL SERVER client settings of the normal working client and the failed client, it is found that the working client uses the protocol "Named pipes" as the priority, uses the name of the server to connect to the database server, and the failed client uses the protocol enabled first with "tcp/ip". The IP address of the server is used to connect to the database server. The default port is 1433. Set "Named pipes" to the priority enabled protocol on the failed client, and connect to the database server using the name of the server, then the connection is normal and can work properly. As a result, it is determined that the fault is related to the TCP/IP protocol, and run the netstat-an command on the server (Windows 2000 SERVER SP4+SQL Server 2000 last IP address 10.140.90.249), and the results are as follows:

As can be seen from the above, port 1433 is not open in the TCP/IP protocol on the server. Search the Internet for information about SQL Server and port 1433. It is found that SQL Server 2000 opens port 1433 by default, while SQL Server 2000 turns off port 1433 by default before SP4. Ask the administrator that the SP4 patch of SQL Server 2000 has been installed on the server, because the version number of SQL Server 2000 is not displayed in about. So go to query Analyzer to check the version number of SQL Server 2000 and execute it in query Analyzer:

SELECT @ @ VERSION

The return value is "8.00.194 RTM", which is the original version of SQL Server 2000. Further ask the administrator that the SQL Server service on the server is not stopped during the installation of SP4, while the SQL Server 2000 SP4 explicitly requires that the SQL Server service on the server and all client programs should be stopped before installation, thus judging that the SQL Server 2000 SP4 on the server is not installed successfully. The relationship between SQL Server 2000 version and version number can be found online.

Reinstall SQL Server 2000 SP4 on the server, prompting "the previous program installation created a pending file operation. You must restart your computer before running the program." Indicates that the previous SP4 was not installed successfully, restart the server, this prompt continues, start the registry editor, go to the HKEY_LOCAL_MACHINE\ SYSTEM\ CurrentControlSet\ Control\ Session Manager branch, delete the PendingFileRenameOperations project, and then reinstall SQL Server 2000 SP4 successfully. Then execute the netstat-an command on the server, port 1433 is listed impressively, is in the "LISTENING" state, sets the faulty client to the TCP/IP connection mode, starts the program, the connection completes smoothly, and the error message no longer appears.

3 concluding remarks

At present, the software system is becoming more and more complex, and more and more systems are involved. when troubleshooting, we can not be confused by the superficial phenomenon of the fault, we should follow the tree, analyze and eliminate it step by step, and go to the forums and official websites of the software system to understand the information about the relevant products, especially the patch information. Only when troubleshooting can we get twice the result with half the effort and avoid detours.

This kind of failure can also occur in the stand-alone state. Generally, the client TCP/IP of SQL SERVER is set to the protocol enabled first, and the IP address is used to connect to SQL SERVER. When there is a problem with the physical connection of the network cable or when there is a problem with the IP address setting.

These are the troubleshooting methods for the non-existence or denial of access to SQL Server. The editor believes that there are some knowledge points that we may see or use in our daily work. I hope you can learn more from this article. For more details, please follow the industry information channel.

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