database suspend

database suspend
ref:  --http://asktom.oracle.com/pls/apex/f?p=100:11:0::::P11_QUESTION_ID:373618158622
from Tom
"
The basic steps for using SUSPEND and RESUME are as follows:
Place the database tablespaces in hot backup mode using the ALTER TABLESPACE BEGIN BACKUP
statement. For example, to place tablespace USERS in hot backup mode enter:

ALTER TABLESPACE users BEGIN BACKUP;


       
If your mirror system has problems with splitting a mirror while disk writes are
occurring, issue the following:

ALTER SYSTEM SUSPEND;
   

       
Split your mirrors at the O/S or hardware level.

Issue the following:

ALTER SYSTEM RESUME;
   

       
Take the specified tablespaces out of hot backup mode. For example, to take tablespace
USERS out of hot backup mode enter:

ALTER TABLESPACE users END BACKUP;
   

       
Copy the control file and archive the online redo logs as usual for a backup.

"