Scenario

Troubleshooting host name changes. When the machine name is changed where we have installed SQL Server, all the instances services are started but replication, Jobs, Alerts, Maintenance plans causes errors. Hence we have to rename the instance.

Solution

To rename instance we can use the following SP

1. Check the old server name as follows

SELECT@@servername

2. Drop the server and add the new server name

SP_DROPSERVER <oldName>

SP_ADDSERVER <newName>, local

3. Restart the instance
4. Check the server name again

SELECT @@servername

Reference Source – Microsoft

There are a few potential impacts to consider when changing the name of a SQL Server instance:

1. If you have any applications that connect to the instance using the old name, those connections will no longer work and will need to be updated to use the new name.
2. Any scripts or other processes that rely on the old instance name will also need to be updated to use the new name.
3. If you are using SQL Server Management Studio to connect to the instance, you will need to update the connection information to use the new instance name.
4. If you have configured any linked servers to connect to the instance, those linked servers will need to be updated to use the new instance name.
5. If you have configured any distributed queries or distributed transactions that involve the instance, those configurations will need to be updated to use the new instance name.

It is a good idea to carefully plan and test the impact of changing the instance name before making the change in a production environment.