KingbbaseES V8R6集群维护案例之---集群之间数据迁移

案例说明：
生产环境是集群环境，测试环境是集群，现需要将生产环境的数据迁移到测试集群中运行，本文档详细介绍了从集群环境迁移数据的操作步骤，可以作为生产环境迁移数据的参考。

适用版本： KingbaseES V8R6

本案例数据库版本(集群使用相同的版本)：

test=# select version();
                                                       version
----------------------------------------------------------------------------------------------------------------------
 KingbaseES V008R006C005B0041 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-46), 64-bit
(1 row)

生产集群节点信息：

[kingbase@node1 bin]$ ./repmgr cluster show
 ID | Name  | Role    | Status    | Upstream | Location | Priority | Timeline | Connection string                                   
----+-------+---------+-----------+----------+----------+----------+----------+----------------------------------------------------------------------------------------------------------------------------------------------------
 1  | node1 | primary | * running |          | default  | 100      | 1        | host=192.168.1.201 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3
 2  | node2 | standby |   running | node1    | default  | 100      | 1        | host=192.168.1.202 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3

测试集群节点信息：

[kingbase@node101 bin]$ ./repmgr cluster show
 ID | Name    | Role    | Status    | Upstream | Location | Priority | Timeline | Connection string                                 
----+---------+---------+-----------+----------+----------+----------+----------+----------------------------------------------------------------------------------------------------------------------------------------------------
 1  | node101 | primary | * running |          | default  | 100      | 13       | host=192.168.1.101 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3
 2  | node102 | standby |   running | node101  | default  | 100      | 13       | host=192.168.1.102 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3

一、生产环境迁移数据前的准备

1、生产环境数据信息

prod=# \l
                             List of databases
   Name    | Owner  | Encoding | Collate  |    Ctype    | Access privileges
-----------+--------+----------+----------+-------------+-------------------
 esrep     | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 prod      | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 prod1     | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 prod2     | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 security  | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 template0 | system | UTF8     | ci_x_icu | zh_CN.UTF-8 | =c/system        +
           |        |          |          |             | system=CTc/system
 template1 | system | UTF8     | ci_x_icu | zh_CN.UTF-8 | =c/system        +
           |        |          |          |             | system=CTc/system
 test      | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
(8 rows)
 
prod=# select count(*) from t2;
 count
--------
 100000
(1 row)

2、关闭生产集群

[kingbase@node1 bin]$ ./sys_monitor.sh stop
2022-06-20 16:00:46 Ready to stop all DB ...
.......
2022-06-20 16:01:02 DB on "[192.168.1.202]" stop success.
2022-06-20 16:01:02 begin to stop DB on "[192.168.1.101]".
waiting for server to shut down....... done
server stopped
2022-06-20 16:01:06 DB on "[192.168.1.201]" stop success.
2022-06-20 16:01:06 Done.

二、迁移生产数据到测试环境

Tips：
1)将生产数据迁移到集群，需要停止生产数据库服务，根据data目录数据的大小，要估算停机窗口时间。
2)在生产数据库前，建议手工创建检查点，如果wal日志比较大，建议备份后，清理wal日志，只需要保留最近一天的日志到最近检查点后即可。
3)需要跨主机将生产库主库data目录拷贝到集群的主备库节点，需 根据网络带宽和节点数，估算整个拷贝时间。

1、关闭测试集群

[kingbase@node101 bin]$ ./sys_monitor.sh stop
2022-06-20 16:10:46 Ready to stop all DB ...
 
2022-06-20 16:11:02 DB on "[192.168.1.102]" stop success.
2022-06-20 16:11:02 begin to stop DB on "[192.168.1.101]".
waiting for server to shut down....... done
server stopped
2022-06-20 16:11:06 DB on "[192.168.1.101]" stop success.
2022-06-20 16:11:06 Done.

2、将测试库数据备份[kingbase@node101 kingbase]$ mv data data.bk

3、拷贝生产集群主库data到测试集群主备库(所有节点)

1)拷贝生产数据到测试库

[kingbase@node1 kingbase]$ scp -r data node101:/home/kingbase/cluster/R6HA/kha/kingbase/
[kingbase@node1 kingbase]$ scp -r data node102:/home/kingbase/cluster/R6HA/kha/kingbase/

2)备库创建standby.signal[kingbase@node102 data]$ touch standby.signal

3)复制测试集群的数据库配置文件：(所有节点)

[kingbase@node101 data]$ cp ../data.bk/kingbase.auto.conf ./
[kingbase@node101 data]$ cp ../data.bk/kingbase.conf ./
[kingbase@node101 data]$ cp ../data.bk/es_rep.conf ./
 
# 查看kingbase.auto.conf
[kingbase@node101 data]$ cat kingbase.auto.conf
# Do not edit this file manually!
# It will be overwritten by the ALTER SYSTEM command.
enable_upper_colname = 'on'
wal_retrieve_retry_interval = '5000'
primary_conninfo = 'user=system connect_timeout=10 host=192.168.1.102 port=54321 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3 application_name=node101'
recovery_target_timeline = 'latest'
primary_slot_name = 'repmgr_slot_1'
synchronous_standby_names = ''

三、重新注册集群节点

Tips：
因为data数据中存储的是原生产集群的节点信息(esrep库)，所以要根据测试库的repmgr.conf文件重新注册节点。

1、启动主备库数据库服务

[kingbase@node101 bin]$ ./sys_ctl restart -D ../data
waiting for server to shut down.... done
.......
server started

2、查看节点状态信息

[kingbase@node101 bin]$ ./repmgr cluster show
 ID | Name  | Role    | Status        | Upstream | Location | Priority | Timeline | Connection string                               
----+-------+---------+---------------+----------+----------+----------+----------+----------------------------------------------------------------------------------------------------------------------------------------------------
 1  | node1 | primary | ? unreachable |          | default  | 100      | ?        | host=192.168.1.201 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3
 2  | node2 | standby | - failed      | node1    | default  | 100      | ?        | host=192.168.1.202 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3
 
WARNING: following issues were detected
  - unable to connect to node "node1" (ID: 1)
  - node "node1" (ID: 1) is registered as an active primary but is unreachable
  - unable to connect to node "node2" (ID: 2)
 
# 如上所示，因为repmgr.conf和esrep库的注册信息不一致，现在集群节点处于非正常状态。

3、重新注册主备库1)注册主库

[kingbase@node101 bin]$ ./repmgr primary register --force
INFO: connecting to primary database...
INFO: "repmgr" extension is already installed
NOTICE: primary node record (ID: 1) updated
 
[kingbase@node101 bin]$ ./repmgr cluster show
 ID | Name    | Role    | Status    | Upstream | Location | Priority | Timeline | Connection string                                 
----+---------+---------+-----------+----------+----------+----------+----------+----------------------------------------------------------------------------------------------------------------------------------------------------
 1  | node101 | primary | * running |          | default  | 100      | 1        | host=192.168.1.101 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3
 2  | node2   | standby | - failed  | node101  | default  | 100      | ?        | host=192.168.1.202 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3
 
WARNING: following issues were detected
  - unable to connect to node "node2" (ID: 2)

2)注册备库

[kingbase@node102 bin]$ ./repmgr standby register --force
INFO: connecting to local node "node102" (ID: 2)
INFO: connecting to primary database
INFO: standby registration complete
 
NOTICE: standby node "node102" (ID: 2) successfully registered
[kingbase@node102 bin]$ ./repmgr cluster show
 ID | Name    | Role    | Status    | Upstream | Location | Priority | Timeline | Connection string                                 
----+---------+---------+-----------+----------+----------+----------+----------+----------------------------------------------------------------------------------------------------------------------------------------------------
 1  | node101 | primary | * running |          | default  | 100      | 1        | host=192.168.1.101 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3
 2  | node102 | standby |   running | node101  | default  | 100      | 1        | host=192.168.1.102 user=system dbname=esrep port=54321 connect_timeout=10 keepalives=1 keepalives_idle=10 keepalives_interval=1 keepalives_count=3
 
 # 如上所示，节点注册完成后，集群节点状态正常。

四、查看流复制状态

Tips：
如果生产集群和测试集群的流复制复制槽名称不一致，可能需要重建复制槽。

# 复制槽信息
test=# select * from sys_replication_slots;
   slot_name   | plugin | slot_type | datoid | database | temporary | active | active_pid | xmin | catalog_xmin | restart_lsn | confirmed_flush_lsn
---------------+--------+-----------+--------+----------+-----------+--------+------------+------+--------------+-------------+---------------------
 repmgr_slot_2 |        | physical  |        |          | f         | t      |      26620 |  963 |              | 0/4E000FB8  |
 repmgr_slot_1 |        | physical  |        |          | f         | f      |            |      |              |             |
(2 rows)
 
# 流复制状态信息
test=# select * from sys_stat_replication;
  pid  | usesysid | usename | application_name |  client_addr  | client_hostname | client_port |         backend_start         | backend_xmin |   state   |  sent_lsn  | write_lsn  | flush_lsn  | replay_lsn | write_lag | flush_lag | replay_lag | sync_priority | sync_state |          reply_time
-------+----------+---------+------------------+---------------+-----------------+-------------+-------------------------------+----
 
 26620 |       10 | system  | node102          | 192.168.1.102 |                 |       49454 | 2022-06-20 17:08:15.347515+08 |          | streaming | 0/4E000FB8 | 0/4E000FB8 | 0/4E000FB8 | 0/4E000FB8 |           |           |            |             1 | sync       | 2022-06-20 17:11:44.277666+08
(1 row)

五、验证数据

1、查看迁移后数据

test=# \l
                             List of databases
   Name    | Owner  | Encoding | Collate  |    Ctype    | Access privileges
-----------+--------+----------+----------+-------------+-------------------
 esrep     | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 prod      | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 prod1     | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 prod2     | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 security  | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
 template0 | system | UTF8     | ci_x_icu | zh_CN.UTF-8 | =c/system        +
           |        |          |          |             | system=CTc/system
 template1 | system | UTF8     | ci_x_icu | zh_CN.UTF-8 | =c/system        +
           |        |          |          |             | system=CTc/system
 test      | system | UTF8     | ci_x_icu | zh_CN.UTF-8 |
(8 rows)
 
prod=# select count(*) from t2;
 count
--------
 100000
(1 row)

2、重启集群

[kingbase@node101 bin]$ ./sys_monitor.sh restart
2022-06-20 17:12:39 Ready to stop all DB ...
.......
2022-06-20 17:13:14 repmgrd on "[192.168.1.102]" start success.
 ID | Name    | Role    | Status    | Upstream | repmgrd | PID   | Paused? | Upstream last seen
----+---------+---------+-----------+----------+---------+-------+---------+--------------------
 1  | node101 | primary | * running |          | running | 28907 | no      | n/a
 2  | node102 | standby |   running | node101  | running | 26280 | no      | 2 second(s) ago
[2022-06-20 17:13:19] [NOTICE] redirecting logging output to "/home/kingbase/cluster/R6HA/kha/kingbase/log/kbha.log"
 
[2022-06-20 17:13:22] [NOTICE] redirecting logging output to "/home/kingbase/cluster/R6HA/kha/kingbase/log/kbha.log"
 
2022-06-20 17:13:29 Done.

六、总结

1、从集群环境迁移数据，如果需要保证数据一致，必须要将集群停库，对于生产环境，要考虑停机窗口。
 2、如果需要将目标集群数据重新加载到新的集群，需要将目标集群数据做逻辑备份，但是在导入时如果有重复数据需注意处理。(如将测试数据再导入到迁移后的集群中，可能有许多数据会重复)。
 3、申请停机窗口，要考虑源集群数据量的大小、主机间的网络带宽、集群节点数、集群配置时间、集群启动故障的处理时间等。