Connect to the partner server that you want to move and ensure that it has the mirror role. You can only move the partner with the mirror role. If the server you want to move to is the primary server, you must initiate a failover so that the primary and mirror servers switch roles

Create a new directory for the new partner server.

Connect to the primary server.

Drop the partner definition for the server being moved by executing a DROP MIRROR SERVER statement.

The mirror database stops. If the mirror database is the only database running on the server, then the server also stops.

Create a new partner definition for the server to become the new partner. For example, execute the following statement:

CREATE MIRROR SERVER mirror_server3 AS PARTNER 
connection_string='SERVER=demo_server3;HOST=localhost:6874' 
state_file='c:\\server3\\server3.state'; 

Update the primary and mirror definitions. For example, execute the following statements:

ALTER MIRROR SERVER mirror_demo_primary AS PRIMARY 
connection_string='SERVER=mirror_demo_primary;HOST=localhost:6871,localhost:6874';

ALTER MIRROR SERVER mirror_demo_mirror AS MIRROR
connection_string='SERVER=mirror_demo_mirror;HOST=localhost:6871,localhost:6874';

Make copies of the primary database file and transaction log and add them to the new partner server directory. For example, run the following command:

dbbackup -c "UID=DBA;PWD=sql;SERVER=mirror_server1;DBN=mirror_demo" server3

Start the new partner server with the -xp on option so that the new partner can join the mirroring system. For example, run the following command:

dbsrv16 -n mirror_server3 -x "tcpip(PORT=6874)" -su sql "c:\server3\mirror_demo.db" -xp on

Connect to the new partner server and verify that it is the mirror server.