In the Windows system with ODBC connection

The database alias still exists when the connected data fails, but the connection is still re-established with this alias

In Windows client, with input Db2cmd
Input C:\USERS\YEXUXIA>DB2 List db directory

Display database aliases, database names, node names

C:\USERS\YEXUXIA>DB2 List Node Directory

You can see the client's current connection configuration for the node, node name, entry type (local), Protocol service name

Note: The node directory is used to store all connectivity information for the remote database.

Register the database information :

C:\USERS\YEXUXIA>DB2 Catalog db Cashman as cashman1 at node NDE2BEF5

This means that the database Cashman under the registered node name NDE2BEF5 is locally named Cashman1
The sql1005n database alias "Cashman1" already exists in the local database directory or in the system database directory.

Delete the local entry name:

C:\USERS\YEXUXIA>DB2 Uncatalog DB CASHMAN1

The previous command is to delete the alias locally cashman1
db20000i uncatalog DATABASE Command completed successfully.
db21056w The directory changes will not take effect until the directory cache is refreshed.

You can then connect by continuing the configuration in ODBC.