NDB Cluster的备份和恢复-CFANZ编程社区

这里介绍在线备份NDB Cluster，除了可以通过正常mysqldump的工具来备份NDB集群之外，也可以通过ndb_mgm工具来备份NDB Cluster。

备份

mysqldump工具备份

在任意一个SQL计算节点来备份即可，以下来备份cndba数据库。

备份cndba库

[root@NDB-SQL1 mysql]# mysqldump -uroot -p cndba > /tmp/cndba.sql

Enter password:

查看备份内容

备份内容和备份其他单实例数据库没什么区别。

[root@NDB-SQL1 mysql]# cat /tmp/cndba.sql

-- MySQL dump 10.13 Distrib 5.7.20-ndb-7.5.8, for linux-glibc2.12 (x86_64)

-- Host: localhost Database: cndba

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

-- Server version 5.7.20-ndb-7.5.8-cluster-gpl

/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;

/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;

/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;

/*!40101 SET NAMES utf8 */;

/*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */;

/*!40103 SET TIME_ZONE='+00:00' */;

/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;

/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;

/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;

/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;

-- Table structure for table `sihong`

DROP TABLE IF EXISTS `sihong`;

/*!40101 SET @saved_cs_client = @@character_set_client */;

/*!40101 SET character_set_client = utf8 */;

CREATE TABLE `sihong` (

`id` int(11) DEFAULT NULL,

`name` varchar(50) DEFAULT NULL

) ENGINE=ndbcluster DEFAULT CHARSET=latin1;

/*!40101 SET character_set_client = @saved_cs_client */;

-- Dumping data for table `sihong`

LOCK TABLES `sihong` WRITE;

/*!40000 ALTER TABLE `sihong` DISABLE KEYS */;

INSERT INTO `sihong` VALUES (1,'ruyan'),(4,'dongsheng'),(3,'dongsheng'),(2,'wenqing');

/*!40000 ALTER TABLE `sihong` ENABLE KEYS */;

UNLOCK TABLES;

/*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */;

/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;

/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;

/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;

/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;

/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;

/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;

/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;

-- Dump completed on 2017-12-13 16:33:24

ndb_mgm来备份

官方文档：https://dev.mysql.com/doc/refman/5.7/en/mysql-cluster-backup-concepts.html

在管理节点上输入ndb_mgm，然后通过start backup命令来备份。

查看帮助信息

ndb_mgm> ?

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

NDB Cluster -- Management Client -- Help

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

HELP Print help text

HELP COMMAND Print detailed help for COMMAND(e.g. SHOW)

SHOW Print information about cluster

CREATE NODEGROUP <id>,<id>... Add a Nodegroup containing nodes

DROP NODEGROUP <NG> Drop nodegroup with id NG

START BACKUP [NOWAIT | WAIT STARTED | WAIT COMPLETED]

START BACKUP [<backup id>] [NOWAIT | WAIT STARTED | WAIT COMPLETED]

START BACKUP [<backup id>] [SNAPSHOTSTART | SNAPSHOTEND] [NOWAIT | WAIT STARTED | WAIT COMPLETED]

Start backup (default WAIT COMPLETED,SNAPSHOTEND)

ABORT BACKUP <backup id> Abort backup

SHUTDOWN Shutdown all processes in cluster

PROMPT [<prompt-string>] Toggle the prompt between string specified

or default prompt if no string specified

CLUSTERLOG ON [<severity>] ... Enable Cluster logging

CLUSTERLOG OFF [<severity>] ... Disable Cluster logging

CLUSTERLOG TOGGLE [<severity>] ... Toggle severity filter on/off

CLUSTERLOG INFO Print cluster log information

<id> START Start data node (started with -n)

<id> RESTART [-n] [-i] [-a] [-f] Restart data or management server node

<id> STOP [-a] [-f] Stop data or management server node

ENTER SINGLE USER MODE <id> Enter single user mode

EXIT SINGLE USER MODE Exit single user mode

<id> STATUS Print status

<id> CLUSTERLOG {<category>=<level>}+ Set log level for cluster log

PURGE STALE SESSIONS Reset reserved nodeid's in the mgmt server

CONNECT [<connectstring>] Connect to management server (reconnect if already connected)

<id> REPORT <report-type> Display report for <report-type>

QUIT Quit management client

<report-type> = BACKUPSTATUS | MEMORYUSAGE | EVENTLOG

<level> = 0 - 15

<id> = ALL | Any database node id

For detailed help on COMMAND, use HELP COMMAND.

备份数据包含三部分

Metadata. The names and definitions of all database tables
Table records. The data actually stored in the database tables at the time that the backup was made
Transaction log. A sequential record telling how and when data was stored in the database

开始备份

备份数据

ndb_mgm> start backup;

Waiting for completed, this may take several minutes

Node 3: Backup 1

Node 3: Backup 1 started from node 1 completed

StartGCP: 4256 StopGCP: 4259

#Records: 2062 #LogRecords: 0

Data: 51440 bytes Log: 0 bytes

指定backup-ID备份数据节点

ndb_mgm> start backup 3;

Waiting for completed, this may take several minutes

Node 3: Backup 3 started from node 1

Node 3: Backup 3 started from node 1 completed

StartGCP: 4515 StopGCP: 4518

#Records: 2062 #LogRecords: 0

Data: 51440 bytes Log: 0 bytes

WAIT和NOWAIT参数

这两个参数很明显就是是否等待备份完成再返回结果。NOWAIT让备份在后台执行，客户端无需等待信息返回。

如：

START BACKUP NOWAIT;
STARTUP BACKUP WAIT STARTED;

压缩备份

注意：要加SNAPSHOTSTART参数，并且配置文件中(config.ini)中启用压缩备份(默认是关闭的)。

如：

START BACKUP WAIT STARTED SNAPSHOTSTART;

Config.ini配置文件中的[ndbd default]下添加

CompressedBackup=true

说明备份日志

在备份日志中，需要注意"Backup 1",它表示该备份的唯一ID，如果做第二次备份，备份ID会变成"Backup 2"。当日志中显示"Node 2: Backup 1 started from node 1 completed"时，本次备份结束。备份的数据保存在每个NDB（数据节点）下，具体路径在$MYSQL_HOME/data/BACKUP/BACKUP-ID

#数据节点1的备份数据，如下：

[root@NDB-DATA1 BACKUP-1]# pwd

/usr/local/mysql/data/BACKUP/BACKUP-1

[root@NDB-DATA1 BACKUP-1]# ll

total 56

-rw-r--r-- 1 root root 26476 Dec 13 16:37 BACKUP-1-0.2.Data

-rw-r--r-- 1 root root 21892 Dec 13 16:37 BACKUP-1.2.ctl

-rw-r--r-- 1 root root 52 Dec 13 16:37 BACKUP-1.2.log

#数据节点2的备份数据，如下：

[root@NDB-DATA2 bin]# cd /usr/local/mysql/data/BACKUP/BACKUP-1/

[root@NDB-DATA2 BACKUP-1]# ll

total 56

-rw-r--r-- 1 root root 25508 Dec 13 16:37 BACKUP-1-0.3.Data

-rw-r--r-- 1 root root 21892 Dec 13 16:37 BACKUP-1.3.ctl

-rw-r--r-- 1 root root 52 Dec 13 16:37 BACKUP-1.3.log

可以发现备份文件的名称中有“.3”“.2”意思是各个节点的nodeid。

可以通过show来查看：

id=2

id=3

其他备份参数

BackupDataBufferSize

The amount of memory used to buffer data before it is written to disk.

BackupLogBufferSize

The amount of memory used to buffer log records before these are written to disk.

BackupMemory

The total memory allocated in a data node for backups. This should be the sum of the memory allocated for the backup data buffer and the backup log buffer.

BackupWriteSize

The default size of blocks written to disk. This applies for both the backup data buffer and the backup log buffer.

BackupMaxWriteSize

The maximum size of blocks written to disk. This applies for both the backup data buffer and the backup log buffer.

恢复

恢复时是一个单独的工具，而不是集成在ndb-mgm中的命令，是ndb_restore恢复程序。该工具位于bin/目录下，复制过来即可。

cp /usr/local/mysql/bin/ndb_restore /usr/local/bin/

官方文档：https://dev.mysql.com/doc/refman/5.7/en/mysql-cluster-programs-ndb-restore.html

删除表sihong

mysql> drop table sihong;

Query OK, 0 rows affected (0.23 sec)

在数据节点1(192.168.1.123)执行恢复命令--恢复元数据

#ndb_restore -b 1 -n 2 -c host=192.168.1.120:1186 -m -r --backup_path=/usr/local/mysql/data/BACKUP/BACKUP-1/

Backup Id = 1

Nodeid = 2

backup path = /usr/local/mysql/data/BACKUP/BACKUP-1/

2017-12-13 17:54:12 [restore_metadata] Read meta data file header

Opening file '/usr/local/mysql/data/BACKUP/BACKUP-1/BACKUP-1.2.ctl'

File size 21892 bytes

Backup version in files: ndb-6.3.11 ndb version: mysql-5.7.20 ndb-7.5.8

2017-12-13 17:54:12 [restore_metadata] Load content

Stop GCP of Backup: 4258

2017-12-13 17:54:12 [restore_metadata] Get number of Tables

2017-12-13 17:54:12 [restore_metadata] Validate Footer

Connected to ndb!!

2017-12-13 17:54:12 [restore_metadata] Restore objects (tablespaces, ..)

2017-12-13 17:54:12 [restore_metadata] Restoring tables

Successfully restored table `cndba/def/sihong`

Successfully restored table event REPL$cndba/sihong

2017-12-13 17:54:12 [restore_metadata] Save foreign key info

Create foreign keys

Create foreign keys done

2017-12-13 17:54:12 [restore_data] Start restoring table data

2017-12-13 17:54:12 [restore_data] Read data file header

Opening file '/usr/local/mysql/data/BACKUP/BACKUP-1/BACKUP-1-0.2.Data'

File size 26476 bytes

2017-12-13 17:54:12 [restore_data] Restore fragments

_____________________________________________________

Processing data in table: mysql/def/ndb_index_stat_sample(7) fragment 0

_____________________________________________________

Processing data in table: sys/def/NDB$EVENTS_0(3) fragment 0

_____________________________________________________

Processing data in table: mysql/def/ndb_apply_status(9) fragment 0

_____________________________________________________

Processing data in table: mysql/def/ndb_index_stat_head(6) fragment 0

_____________________________________________________

Processing data in table: cndba/def/sihong(10) fragment 0

_____________________________________________________

Processing data in table: mysql/def/NDB$BLOB_4_3(5) fragment 0

_____________________________________________________

Processing data in table: sys/def/SYSTAB_0(2) fragment 0

_____________________________________________________

Processing data in table: mysql/def/ndb_schema(4) fragment 0

2017-12-13 17:54:12 [restore_log] Read log file header

Opening file '/usr/local/mysql/data/BACKUP/BACKUP-1/BACKUP-1.2.log'

File size 52 bytes

2017-12-13 17:54:12 [restore_log] Restore log entries

Restored 2 tuples and 0 log entries

NDBT_ProgramExit: 0 - OK

参数说明：

-b	Backupid
-n	nodeid
-c	--connectstring的别名
-m	元数据
-r	restore恢复
--backup_path	备份文件所在目录

更多参数参考官方文档：

https://dev.mysql.com/doc/refman/5.7/en/mysql-cluster-programs-ndb-restore.html

在数据节点2(192.168.1.124)恢复数据内容

注意：这里不要加“-m”参数了，因为不需要再恢复元数据了。

[root@NDB-DATA2 BACKUP-1]# ndb_restore -b 1 -n 3 -c host=192.168.1.120:1186 -r /usr/local/mysql/data/BACKUP/BACKUP-1/

Backup Id = 1

Nodeid = 3

backup path = /usr/local/mysql/data/BACKUP/BACKUP-1/

2017-12-13 17:58:00 [restore_metadata] Read meta data file header

Opening file '/usr/local/mysql/data/BACKUP/BACKUP-1/BACKUP-1.3.ctl'

File size 21892 bytes

Backup version in files: ndb-6.3.11 ndb version: mysql-5.7.20 ndb-7.5.8

2017-12-13 17:58:00 [restore_metadata] Load content

Stop GCP of Backup: 4258

2017-12-13 17:58:00 [restore_metadata] Get number of Tables

2017-12-13 17:58:00 [restore_metadata] Validate Footer

Connected to ndb!!

2017-12-13 17:58:01 [restore_metadata] Restore objects (tablespaces, ..)

2017-12-13 17:58:01 [restore_metadata] Restoring tables

2017-12-13 17:58:01 [restore_metadata] Save foreign key info

2017-12-13 17:58:01 [restore_data] Start restoring table data

2017-12-13 17:58:01 [restore_data] Read data file header

Opening file '/usr/local/mysql/data/BACKUP/BACKUP-1/BACKUP-1-0.3.Data'

File size 25508 bytes

2017-12-13 17:58:01 [restore_data] Restore fragments

_____________________________________________________

Processing data in table: mysql/def/ndb_index_stat_sample(7) fragment 1

_____________________________________________________

Processing data in table: sys/def/NDB$EVENTS_0(3) fragment 1

_____________________________________________________

Processing data in table: mysql/def/ndb_apply_status(9) fragment 1

_____________________________________________________

Processing data in table: mysql/def/ndb_index_stat_head(6) fragment 1

_____________________________________________________

Processing data in table: cndba/def/sihong(10) fragment 1

_____________________________________________________

Processing data in table: mysql/def/NDB$BLOB_4_3(5) fragment 1

_____________________________________________________

Processing data in table: sys/def/SYSTAB_0(2) fragment 1

_____________________________________________________

Processing data in table: mysql/def/ndb_schema(4) fragment 1

2017-12-13 17:58:01 [restore_log] Read log file header

Opening file '/usr/local/mysql/data/BACKUP/BACKUP-1/BACKUP-1.3.log'

File size 52 bytes

2017-12-13 17:58:01 [restore_log] Restore log entries

Restored 2 tuples and 0 log entries

NDBT_ProgramExit: 0 - OK

查看表及表中数据

mysql> show tables;

+-----------------+

| Tables_in_cndba |

+-----------------+

| sihong |

+-----------------+

1 row in set (0.00 sec)

mysql> select * from sihong;

+------+-----------+

| id | name |

+------+-----------+

| 1 | ruyan |

| 4 | dongsheng |

| 3 | dongsheng |

| 2 | wenqing |

+------+-----------+

4 rows in set (0.00 sec)

可以看到，数据已经回来了。

还有更多的恢复参数，

例如：

#只恢复指定数据库

--include-databases=db1 --exclude-tables=db1.t1

#只恢复数据库中的指定表

--exclude-tables=db1.t1 --include-databases=db1