ORA-245: In RAC environment from 11.2 onwards Backup Or Snapshot controlfile needs to be in shared location (Doc ID 1472171.1)

巡检时遇到错误如下：

alert日志：

Wed Dec 19 01:00:29 2018
Errors in file /oracle/base/diag/rdbms/usap/usap1/trace/usap1_ora_7078838.trc:
ORA-00245: control file backup failed; target is likely on a local file system
Wed Dec 19 03:12:31 2018
ALTER SYSTEM ARCHIVE LOG

/oracle/base/diag/rdbms/usap/usap1/trace/usap1_ora_7078838.trc 的信息如下:

Trace file /oracle/base/diag/rdbms/usap/usap1/trace/usap1_ora_6357166.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options
ORACLE_HOME = /oracle/product/11.2.0.4
System name: AIX
Node name: jnpd-usap-dbrac-01
Release: 1
Version: 7
Machine: 00FB769F4C00
Instance name: usap1
Redo thread mounted by this instance: 1
Oracle process number: 92
Unix process pid: 6357166, image: oracle@jnpd-usap-dbrac-01 (TNS V1-V3)

*** 2019-01-18 03:13:18.387
*** SESSION ID:(7637.2713) 2019-01-18 03:13:18.387
*** CLIENT ID:() 2019-01-18 03:13:18.387
*** SERVICE NAME:(SYS$USERS) 2019-01-18 03:13:18.387
*** MODULE NAME:(rman@jnpd-usap-dbrac-01 (TNS V1-V3)) 2019-01-18 03:13:18.387
*** ACTION NAME:(0000012 STARTED114) 2019-01-18 03:13:18.387

ORA-00245: control file backup failed; target is likely on a local file system

===================================================================================================================

下面为官方文档：

ORA-245: In RAC environment from 11.2 onwards Backup Or Snapshot controlfile needs to be in shared location (Doc ID 1472171.1)

APPLIES TO:

Oracle Database - Enterprise Edition - Version 11.2.0.1.0 and later
Information in this document applies to any platform.
This issue is only applicable to RAC database.

From 11gR2 onwards, the controlfile backup happens without holding the controlfile enqueue. For non-RAC database, this doesn't change anything. But for RAC database, due to the changes made to the controlfile backup mechanism in 11gR2, any instance in the cluster may write to the snapshot controlfile. Due to this snapshot controlfile need to be visible to all instances.

从11 gR2开始，控制文件备份将在不持有控制文件队列的情况下进行。对于非RAC数据库，这不会改变任何事情。但是对于RAC数据库，由于对11 gR2中的控制文件备份机制所做的更改，集群中的任何实例都可以写入快照控制文件。因此，快照控制文件需要对所有实例都是可见的。

The snapshot controlfile MUST be accessible by all nodes of a RAC database, if the snapshot controlfile does not reside on a shared device error will be raised at the time of RMAN backup while taking snapshot of controlfile.
快照控制文件必须可由RAC数据库的所有节点访问，如果快照控制文件不驻留在共享设备上，则在RMAN备份时，在获取快照控制文件时将引发错误。

This applies to backing up controlfile using sqlplus / having autobackup of controlfile configured on non
shared location.

ORA-245 error message description
----------------------------------------
00245, 00000, "control file backup operation failed"
*Cause: Failed to create a control file backup because some process
signaled an error during backup creation.
*Action: Check alert files for further information. This usually happens
because some process could not access the backup file during
backup creation. Any process of any instance that starts a
read/write control file transaction must have an access to the
backup control file during backup creation.

DESCRIPTION

1. In RAC environment controlfile autobackup fails with ora-0245

Autobackup of controlfile in RMAN is failing with error:
RMAN-571: ===========================================================
RMAN-569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-571: ===========================================================
RMAN-3009: failure of Control File and SPFILE Autobackup command on
ORA_DISK_1 channel at 10/27/2010 12:13:31
ORA-245: control file backup operation failed

2. In RAC environment, backup controlfile to non shared location fails

SQL> ALTER DATABASE BACKUP CONTROLFILE TO '/home/rac1122/test/control.bk' REUSE
*
ERROR at line 1:
ORA-245: control file backup operation failed

3. In RAC environment backing up standby controlfile to non shared location fails

SQL> alter database create standby controlfile as '/home/oracle/renostdbycntrl.ctl';

alter database create standby controlfile as
'/home/oracle/renostdbycntrl.ctl'
*
ERROR at line 1:
ORA-245: control file backup operation failed

4. In RAC environment copy current controlfile to '${DB_BACKUP_DIR}/rac_tnctv_control.bak';

channel ch1: starting datafile copy
copying current control file
RMAN-571: ===========================================================
RMAN-569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-571: ===========================================================
RMAN-3009: failure of backup command on 10/07/2011 11:36:42 channel at ch1
ORA-245: control file backup operation failed

5. In RAC environment, Rman backup fails if snapshot controlfile is not in shared location.

RMAN-00571: ========================================================
RMAN-00569: ============ ERROR MESSAGE STACK FOLLOWS =============
RMAN-00571: =========================================================
RMAN-03009: failure of resync command on default channel at 03/13/2012 10:19:41
ORA-00245: control file backup operation failed

6. In RAC environment, with NO RMAN activity, but controlfile autobackup is being created by database structure change. I.e., adding datafiles or a resize of datafiles with autoextend. Alert.log shows:

2016-12-30 23:46:10.244000 +00:00
Errors in file /ora01/app/oracle/diag/rdbms/persprop/persprop5/trace/persprop5_m000_24118.trc:
ORA-19624: operation failed, retry possible
ORA-19504: failed to create file "/orabck/uhilsfmt/persprop1/rman/c-3364950485-20161230-00.cf"
ORA-27040: file create error, unable to create file
SVR4 Error: 2: No such file or directory
Additional information: 1

OCCURRENCE

Only affect Real application Cluster (RAC), 11.2 onward.

SYMPTOMS

In RAC environment any form of controlfile backup may fail with ORA-0245 if the location of the Snapshot Controlfile is not a shared location. The backup of the controlfile actualy makes a backup of the SNAPSHOT controlfile. The Snapshot controlfile is created when the controlfile is about to be backed up. The Snapshot controlfile is a read-consistent copy of the controlfile.

NOTE: There is another issue in which this error occurs when the backup location is not shared, see RMAN BACKUP TO LOCAL DEVICE WITH SNAPSHOT ON SHARED FAILS ORA-00245 (Doc ID 1516654.1)

According to bug 18073805 (closed as not a bug), ORA-00227 can also be raised from "alter database backup controlfile to <file>" when the location of the file is not shared.

WORKAROUND

SOLUTION:

This is a RAC specific 'configuration' issue and the correct configuration is as described below

It is changed behaviour which requires that the snapshot controlfile in a RAC environment, is on a shared location.

1. Check the snapshot controlfile location:

RMAN> show snapshot controlfile name;

2. Configure the snapshot controlfile to a shared disk:

RMAN> CONFIGURE SNAPSHOT CONTROLFILE NAME TO '<shared_disk>/snapcf_<DBNAME>.f';

Or in case of ASM use

RMAN> CONFIGURE SNAPSHOT CONTROLFILE NAME TO '+<DiskGroup>/snapcf_<DBNAME>.f';

PATCHES

HISTORY

02-07-2012 created and Published alert

07-12-2015 updated

REFERENCES

BUG:12311429 - ALTER DATABASE BACKUP CONTROLFILE FAILS WITH ORA-245
NOTE:265623.1 - RESYNC CATALOG fails with ORA-15045
NOTE:1516654.1 - RMAN BACKUP TO LOCAL DEVICE WITH SNAPSHOT ON SHARED FAILS ORA-00245
BUG:13085539 - ORA-245 OCCURS DURING RMAN COPY CORRENT CONTROLFILE.
BUG:13780443 - CONTROLFILE BACKUP MUST RESIDE ON SHARED DEVICE WITH RAC DATABASE
NOTE:16012614.8 - Bug 16012614 - ORA-245 on RMAN controlfile backup

BUG:17824928 - ORA-00245 ERROR RMAN BACKUP WITH SNAPSHOT ON SHARED FAILS
BUG:18073805 - ORA-227: CORRUPT BLOCK DETECTED IN CONTROL FILE

BUG:10263733 - SNAPSHOT CONTROLFILE USED BY RMAN MUST RESIDE ON SHARED DEVICE FOR RAC DATABASE
BUG:10252378 - CONTROLFILE AUTOBACKUP FAILS WITH ORA-00245: CONTROL FILE BACKUP OPERATION FAILE
BUG:16012614 - ORA-245 ON RMAN CONTROLFILE BACKUP ON LOCAL DEVICE WITH SNAPSHOT ON SHARED