Dataguard closes state enable repository: Sql>startup Nomount; Sql>alter database mount standby database; Sql>alter database recover managed standby database disconnect from session; (synchronous but not real-time application log) Close standby: Sql>alter database Recover managed standby database cancel; Sql>shutdown immediate; Open from closed state: Sql>startup Nomount; Sql>alter database mount standby database; Sql>alter database open Read only; read-only opened from recovery state: sql>sql>sql>alter database recover managed standby database using current logfile disconnect from session; (Sync and live Application log) ------------------------------------------------------------------------main repository switchover: Main Library:sql> ALTER DATABASE commit to switchover to physical standby; Sql>shutdown immediate; Sql>startup Nomount; Sql>alter database mount standby database; Sql>alter database recover managed standby database disconnect from session; Prepare library: Sql>alter database commit to SW Itchover to Primary; Sql>shutdown immediate; Sql>startUp,------------------------------------------------------------------ non-normal switch: (when the main library when the machine) to start the Fallover standby library:sql> ALTER DATABASE recover managed standby database finish; Sql>alter database commit to switchover to primary; Sql>shutdown immediate; sql>startup;-----------------------------------------------------------------Routine Maintenance commands: querying database status:sql> Select Instance_name,status from v$instance; querying the Master repository:sql> select Database_role from v$database; Check the switchable state of the database: Sql>select switchover_status from v$database; archive a log: Alter system switch logfile; Whether the query archive log is applied:sql> select sequence#,dest_id,first_time,next_time,archived,applied from v$archived_log; Check if the standby is synchronized with the main library:sql> select archived_thread#,archived_seq#,applied_thread#,applied_seq# from V$archive_dest_status; Query Log shipping conditions:sql> SELECT * from v$archive_gap; queries the current host run state:sql> select Switchover_status,database_role, Protection_mode from v$database; View some process conditions and processes for the current repository idsql> select Process,status,thread#,sEquence#,block#,blocks from v$managed_standby; View synchronization error condition:sql> Select error from v$archive_dest; Verify the archived files that are passed:sql> select Sequence#,first_time,next_time,applied,completion_time from V$archived_log ORDER by sequence#; the maximum number of archived files for the main repository is the same;sql> select DISTINCT Thread#,max (sequence#) over (partition by thread#) A from v$ archived_log; ------------------------------------------------------------------ Master repository switching: Main Library: Check the switchable state of the database: Sql>select switchover_status from v$database; if it is to standby it can switch normally, ALTER DATABASE Commit to switchover to physical standby, or sessions active, indicates that a session is currently active. ALTER DATABASE commit to switchover to physical standby with session shutdown; The library is modified to standby Standby: Restart the main library shutdown immediate;startup mount; Check the switchable state of the repository: select Switchover_status from v$database; if it is to Primary can switch normally, alter database commit to switchover to primary, if sessions active: Alter database & Nbsp;commit to SwitchoveR to Primary with session shutdown; Run the complete fallback into the main library: -------------------------------------------------- --------------------Main Vault Open log: sql>show parameter Log_archive_dest_state_;alter system set log_archive_dest_state_2= Enable Scope=both;-------------------------------------------------------------------Open Standby Sql>alter database Recover managed Standby database using current logfile disconnect from session;alter database recover managed Standby data Base Cancel;alter Database open;alter database recover managed standby database using current logfile disconnect from Sess ion; --------------------------------------------------------------------------View the protected mode of the database: select Database_ Role,protection_mode,protection_level from V$database; maximum protection: write in the master library while ensuring that it is also written in the standby (MAXIMUM PROTECTION) Maximum availability: Provides maximum protection data without affecting the main library (MAXIMUM availability) maximum performance: not synchronous write, in the case of a good network environment, almost synchronous (MAXIMUM Performance) Modify protection mode: Alter system set log_archive_dest_2= "Service=dg2 ASYNC valid_for= (online_logfiles,pRimary_role) db_unique_name=dg2 "; 1, query the number of connections to Oracle Select count (*) from  V$SESSION;2, querying the number of concurrent connections for Oracle Select count (*) from v$session where status= ' ACTIVE '; 3. View the number of connections for different users Select username,count (username) from v$session where username is not null group by username;4, view all users: Select * from all_users;5, To view user or role system permissions (System permissions that are directly assigned to a user or role): Select * from dba_sys_privs;select * from user_sys_ Privs;6, view roles (view only roles owned by logged-in users) Select * from role_sys_privs;7, view user object permissions:select * From dba_tab_privs;select * from all_tab_privs;select * from user_tab_privs ; 8. View all roles: select * from dba_roles;9, view roles owned by user or role:select * from dba_role_privs; SELECT * FROM USER_ROLE_PRIVS;10, see which users have SYSDBA or Sysoper system permissions (requires appropriate permissions when querying) Select * from v$pwfile_users;
Management of Oracle Data guard
