RMAN备份时遭遇ORA-19571

进行RMAN备份时出现ORA-19571错误，导致备份任务终止，错误提示很明显，是因为在控制文件中没有找到某个归档文件记录，导致备份失

进行RMAN备份时出现ORA-19571错误，导致备份任务终止，具体错误如下：

RMAN-00571: ===========================================================

RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============

RMAN-00571: ===========================================================

RMAN-03002: failure of backup plus archivelog command at 07/10/2015 16:18:43

RMAN-03009: failure of backup command on ORA_DISK_1 channel at 07/10/2015 16:18:24

ORA-19571: archived-log recid 85421 stamp 650564644 not found in control file

错误提示很明显，是因为在控制文件中没有找到某个归档文件记录，导致备份失败，看上去像是控制文件记录被覆盖了。控制文件中的记录分为两类， 一类是循环使用的记录，当记录的solt满时，会覆盖老的记录，记录的保存时间由参数control_file_record_keep_time控制。所以这里首先检查这个参数的设置。

SQL> show parameter control_file

NAME TYPE VALUE

------------------------------------ ----------- ------------------------------

control_file_record_keep_time integer 15
    参数配置为15天，接下来再检查报错中的归档日志的生成时间

SQL> select recid,SEQUENCE#,ARCHIVED,STATUS,COMPLETION_TIME from v$archived_log where recid = 125609;

    RECID SEQUENCE#  ARC S COMPLETION_TIME

---------- ---------- --- - -------------------

    125609 885421    YES A 2015-07-08 02:05:59
    从上面的信息看，归档上两天前生成的，该记录在控制文件中不应该过期。为保证备份任务及时完成，不影响下一天的正常业务，首先手动将归档信息注册到控制文件。

RMAN>catalog start with '/arch1/';
    使用上面的命令注册时，在其中一个节点上提示没有发现可注册的文件，使用下面的命令分别对每个归档文件进行注册

run{

catalog archivelog '/arch1/xxx_1_47849_801075830.dbf';

catalog archivelog '/arch1/xxx_1_47850_801075830.dbf';

...省略部分
catalog archivelog '/arch1/xxx_1_47854_801075830.dbf';

catalog archivelog '/arch1/xxx_1_47855_801075830.dbf';
}
    手动注册后备份成功，但为什么归档信息没有正确的保留在控制文件中，接下来做进一步分析。
  首先检查数据库的alert日志，发现在备份任务失败前出现如下警告：

WARNING: You are creating/reusing datafile /dev/rlvims_control1.

WARNING: Oracle recommends creating new datafiles on devices with zero offset. The command "/usr/sbin/mklv -y LVname -T O -w n -s n -r n VGname NumPPs" can be used. Please contact Oracle customer support for more details.

WARNING: You are creating/reusing datafile /dev/rlvims_control1.

WARNING: Oracle recommends creating new datafiles on devices with zero offset. The command "/usr/sbin/mklv -y LVname -T O -w n -s n -r n VGname NumPPs" can be used. Please contact Oracle customer support for more details.

WARNING: You are creating/reusing datafile /dev/rlvims_control2.

WARNING: Oracle recommends creating new datafiles on devices with zero offset. The command "/usr/sbin/mklv -y LVname -T O -w n -s n -r n VGname NumPPs" can be used. Please contact Oracle customer support for more details.

WARNING: You are creating/reusing datafile /dev/rlvims_control2.

WARNING: Oracle recommends creating new datafiles on devices with zero offset. The command "/usr/sbin/mklv -y LVname -T O -w n -s n -r n VGname NumPPs" can be used. Please contact Oracle customer support for more details.

WARNING: You are creating/reusing datafile /dev/rlvims_control3.

WARNING: Oracle recommends creating new datafiles on devices with zero offset. The command "/usr/sbin/mklv -y LVname -T O -w n -s n -r n VGname NumPPs" can be used. Please contact Oracle customer support for more details.

WARNING: You are creating/reusing datafile /dev/rlvims_control3.

WARNING: Oracle recommends creating new datafiles on devices with zero offset. The command "/usr/sbin/mklv -y LVname -T O -w n -s n -r n VGname NumPPs" can be used. Please contact Oracle customer support for more details.

Expanded controlfile section 28 from 564 to 1128 records

Requested to grow by 564 records; added 3 blocks of records
    这个警告信息是在AIX平台下，，没有将数据库文件放置在零偏移的raw logical volumes设备上，下面对这个错误进行验证：

xxx1>dbfsize /dev/rlvims_control1

Database file: /dev/rlvims_control1

Database file type: raw device

Database file size: 1866 16384 byte blocks

xxx1>dbfsize /dev/rlvims_control2

Database file: /dev/rlvims_control2

Database file type: raw device

Database file size: 1866 16384 byte blocks

xxx1>dbfsize /dev/rlvims_control3

Database file: /dev/rlvims_control3

Database file type: raw device

Database file size: 1866 16384 byte blocks
    发现控制文件所在的设备的确存在偏移，如果没有偏移，会提示Database file type: raw device without 4K starting offset。在AIX中，不同的vg类型决定了不同的lv结构，original valume group在数据落地的时候会产生4k的偏移量，逻辑卷前 4k 用于存储 control block (LVCB)，big volume group在创建裸设备时可以指定参数消除偏移，scalable volume group不会产生偏移，所以，在支持scalable volume group的系统中，一定要建立scalable volume group。
  下面对卷组的类型进行确认：

VOLUME GROUP: vgims VG IDENTIFIER: 00f7614c00004c000000013b4a54f3b1

VG STATE: active PP SIZE: 256 megabyte(s)

VG PERMISSION: read/write TOTAL PPs: 3388 (867328 megabytes)

MAX LVs: 512 FREE PPs: 488 (124928 megabytes)

LVs: 68 USED PPs: 2900 (742400 megabytes)

OPEN LVs: 66 QUORUM: 7 (Enabled)

TOTAL PVs: 12 VG DESCRIPTORS: 12

STALE PVs: 0 STALE PPs: 0

ACTIVE PVs: 12 AUTO ON: no

Concurrent: Enhanced-Capable Auto-Concurrent: Disabled

VG Mode: Concurrent

Node ID: 1 Active Nodes: 2

MAX PPs per VG: 130048

MAX PPs per PV: 1016 MAX PVs: 128

LTG size (Dynamic): 256 kilobyte(s) AUTO SYNC: no

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