[Oracle Active DataGuard 12.1 Installation on Centos 6.7]: Starting switchover on Primary
$ dgmgrl
DGMGRL> connect /
DGMGRL> SHOW DATABASE VERBOSE MASTER
Database - master
Role: PRIMARY
Intended State: TRANSPORT-ON
Instance(s):
orcl12
Properties:
DGConnectIdentifier = 'primary'
ObserverConnectIdentifier = ''
LogXptMode = 'ASYNC'
RedoRoutes = ''
DelayMins = '0'
Binding = 'optional'
MaxFailure = '0'
MaxConnections = '1'
ReopenSecs = '300'
NetTimeout = '30'
RedoCompression = 'DISABLE'
LogShipping = 'ON'
PreferredApplyInstance = ''
ApplyInstanceTimeout = '0'
ApplyLagThreshold = '0'
TransportLagThreshold = '0'
TransportDisconnectedThreshold = '30'
ApplyParallel = 'AUTO'
StandbyFileManagement = 'AUTO'
ArchiveLagTarget = '0'
LogArchiveMaxProcesses = '4'
LogArchiveMinSucceedDest = '1'
DbFileNameConvert = ''
LogFileNameConvert = ''
FastStartFailoverTarget = ''
InconsistentProperties = '(monitor)'
InconsistentLogXptProps = '(monitor)'
SendQEntries = '(monitor)'
LogXptStatus = '(monitor)'
RecvQEntries = '(monitor)'
StaticConnectIdentifier = '(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=moscow.localdomain)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=master_DGMGRL)(INSTANCE_NAME=orcl12)(SERVER=DEDICATED)))'
StandbyArchiveLocation = 'USE_DB_RECOVERY_FILE_DEST'
AlternateLocation = ''
LogArchiveTrace = '0'
LogArchiveFormat = '%t_%s_%r.dbf'
TopWaitEvents = '(monitor)'
Database Status:
SUCCESS
1. Ensure standby redologs are configured on all databases.
SQL> SELECT TYPE, MEMBER FROM V$LOGFILE;
2. Ensure the LogXptMode Property is set to SYNC.
DGMGRL> EDIT DATABASE master SET PROPERTY 'LogXptMode'='SYNC';
DGMGRL> EDIT DATABASE slave SET PROPERTY 'LogXptMode'='SYNC';
3.Specify the FastStartFailoverTarget property
DGMGRL> EDIT DATABASE master SET PROPERTY FastStartFailoverTarget='slave';
DGMGRL> EDIT DATABASE slave SET PROPERTY FastStartFailoverTarget='master';
4.Upgrade the protection mode to MAXAVAILABILITY, if necessary.
DGMGRL> EDIT CONFIGURATION SET PROTECTION MODE AS MAXAVAILABILITY;
5. Enable Flashback Database on the Primary and Standby Databases.
Primary
SQL> ALTER SYSTEM SET UNDO_RETENTION=3600 SCOPE=SPFILE;
SQL> ALTER SYSTEM SET UNDO_MANAGEMENT='AUTO' SCOPE=SPFILE;
SQL> ALTER DATABASE FLASHBACK ON;
Standby
SQL> alter database recover managed standby database cancel;
SQL> ALTER SYSTEM SET UNDO_RETENTION=3600 SCOPE=SPFILE;
SQL> ALTER SYSTEM SET UNDO_MANAGEMENT='AUTO' SCOPE=SPFILE;
SQL> ALTER DATABASE FLASHBACK ON;
SQL> alter database recover managed standby database using current logfile disconnect;
Primary
DGMGRL> ENABLE FAST_START FAILOVER;
Enabled.
DGMGRL> show database master
Database - master
Role: PRIMARY
Intended State: TRANSPORT-ON
Instance(s):
orcl12
Database Warning(s):
ORA-16819: fast-start failover observer not started
Database Status:
WARNING
DGMGRL> START OBSERVER;
[P001 08/15 18:00:40.19] Authentication failed.
DGM-16979: Unable to log on to the primary or standby database as SYSDBA
Failed.
$ dgmgrl
DGMGRL> connect sys/manager@primary
Connected as SYSDBA.
DGMGRL> START OBSERVER;
Observer started
No need to start OBSERVER on the second server.
DGMGRL> show database master
Database - master
Role: PRIMARY
Intended State: TRANSPORT-ON
Instance(s):
orcl12
Database Status:
SUCCESS
DGMGRL> show database slave
Database - slave
Role: PHYSICAL STANDBY
Intended State: APPLY-ON
Transport Lag: 0 seconds (computed 1 second ago)
Apply Lag: 0 seconds (computed 1 second ago)
Average Apply Rate: 60.00 KByte/s
Real Time Query: ON
Instance(s):
orcl12
Database Status:
SUCCESS
DGMGRL> show configuration verbose
Configuration - DG_ORCL12
Protection Mode: MaxAvailability
Members:
master - Primary database
slave - (*) Physical standby database
(*) Fast-Start Failover target
Properties:
FastStartFailoverThreshold = '30'
OperationTimeout = '30'
TraceLevel = 'USER'
FastStartFailoverLagLimit = '30'
CommunicationTimeout = '180'
ObserverReconnect = '0'
FastStartFailoverAutoReinstate = 'TRUE'
FastStartFailoverPmyShutdown = 'TRUE'
BystandersFollowRoleChange = 'ALL'
ObserverOverride = 'FALSE'
ExternalDestination1 = ''
ExternalDestination2 = ''
PrimaryLostWriteAction = 'CONTINUE'
Fast-Start Failover: ENABLED
Threshold: 30 seconds
Target: slave
Observer: moscow.localdomain
Lag Limit: 30 seconds (not in use)
Shutdown Primary: TRUE
Auto-reinstate: TRUE
Observer Reconnect: (none)
Observer Override: FALSE
Configuration Status:
SUCCESS
DGMGRL> switchover to slave;
Performing switchover NOW, please wait...
Operation requires a connection to instance "orcl12" on database "slave"
Connecting to instance "orcl12"...
ORA-01017: invalid username/password; logon denied
Warning: You are no longer connected to ORACLE.
connect to instance "orcl12" of database "slave"
Let’s go
DGMGRL> connect sys/manager@primary
Connected as SYSDBA.
DGMGRL> switchover to slave;
Performing switchover NOW, please wait...
Operation requires a connection to instance "orcl12" on database "slave"
Connecting to instance "orcl12"...
Connected as SYSDBA.
New primary database "slave" is opening...
Oracle Clusterware is restarting database "master" ...
Switchover succeeded, new primary is "slave"
Checking the results
DGMGRL> show configuration
Configuration - DG_ORCL12
Protection Mode: MaxAvailability
Members:
slave - Primary database
master - (*) Physical standby database
Fast-Start Failover: ENABLED
Configuration Status:
SUCCESS (status updated 50 seconds ago)
On the former primary (master)
SQL> select open_mode, database_role from v$database;
OPEN_MODE DATABASE_ROLE
-------------------- ----------------
READ ONLY WITH APPLY PHYSICAL STANDBY
On the former standby (slave)
SQL> select open_mode, database_role from v$database;
OPEN_MODE DATABASE_ROLE
-------------------- ----------------
READ WRITE PRIMARY
Let’s switch logs
SQL> alter system switch logfile;
Both instances have the same number of archive logs.
SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
66
If not, you can enable on the former primary (master)
SQL> alter databaser recover manager current logfile disconnect
Try creating a tablespace on the former standby (slave)
SQL> create tablespace test datafile '+DATA' size 10M autoextend off;
Check the result on the former primary (master)
SQL> select name from v$tablespace;
NAME
------------------------------
SYSTEM
SYSAUX
UNDOTBS1
TEMP
USERS
TEST
6 rows selected.
Switchover back to work as before
$ dgmgrl
DGMGRL> connect sys/manager@primary
DGMGRL> switchover to master;
During switchover, one of the instances went down. I had to manually bring it up and restart the listener. I initially thought I would have to perform the operation again, but it wasn’t necessary.
DGMGRL> show configuration
Configuration - DG_ORCL12
Protection Mode: MaxAvailability
Members:
master - Primary database
slave - (*) Physical standby database
Fast-Start Failover: ENABLED
Configuration Status:
SUCCESS (status updated 13 seconds ago)
DGMGRL> show database master
Database - master
Role: PRIMARY
Intended State: TRANSPORT-ON
Instance(s):
orcl12
Database Status:
SUCCESS
DGMGRL> show database slave
Database - slave
Role: PHYSICAL STANDBY
Intended State: APPLY-ON
Transport Lag: 0 seconds (computed 1 second ago)
Apply Lag: 0 seconds (computed 1 second ago)
Average Apply Rate: 3.00 KByte/s
Real Time Query: ON
Instance(s):
orcl12
Database Status:
SUCCESS
An article helped:
http://oracleinstance.blogspot.ru/2010/01/configuration-of-10g-data-guard-broker.html
What is an OBSERVER and why it is needed, I don’t know yet.
Can it be done simpler? I don’t know that either.