版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/qq_35767346/article/details/54340680
上一篇添加节点的方式，也可以直接加新的seg主机之后新加节点；该篇前半部分讲解了迁移节点，之后根据修改配置文件去添加节点；
1.首先配置互信（在root上和gpadmin上）
（ vi /etc/hosts vi /gp/all_hosts2）
2. 将配置好的.bashrc文件拷贝到新机器
scp .bashrc segment3:`pwd`
3.在新机器建目录，给权限
chown -R gpadmin:gpadmin /data
4.只启动matser
[gpadmin@master~]$ gpstart -m --master 模式
[gpadmin@master～]$ PGOPTIONS="-c gp_session_role=utility" psql --进入utility
xx=#set allow_system_table_mods='dml'; --获得修改权限
5.修改并迁移节点
修改前
#
select * from gp_segment_configuration ;
xx=# SELECT * from gp_segment_configuration ;
dbid | content | role | preferred_role | mode | status | port | hostname | address | replication_port | san_mounts
------+---------+------+----------------+------+--------+-------+----------+----------+------------------+------------
1 | -1 | p | p | s | u | 5432 | master | master | |
2 | 0 | p | p | s | u | 40000 | segment1 | segment1 | 43000 |
4 | 0 | m | m | s | u | 41000 | segment2 | segment2 | 42000 |
3 | 1 | p | p | s | u | 40000 | segment2 | segment2 | 43000 |
5 | 1 | m | m | s | u | 41000 | segment1 | segment1 | 42000 |
(5 rows)
#update gp_segment_configuration set hostname='segment3',address='segment3',status='d' where(content in(0) and role='m'); 将要迁移的节点标记成d
#update gp_segment_configuration set mode='c' where(content in (0) and role ='p');
将down掉的primary的模式从同步S改为改变追踪c
修改后
#
select * from gp_segment_configuration ;
xx=# SELECT * from gp_segment_configuration ;
dbid | content | role | preferred_role | mode | status | port | hostname | address | replication_port | san_mounts
------+---------+------+----------------+------+--------+-------+----------+----------+------------------+------------
1 | -1 | p | p | s | u | 5432 | master | master | |
3 | 1 | p | p | s | u | 40000 | segment2 | segment2 | 43000 |
5 | 1 | m | m | s | u | 41000 | segment1 | segment1 | 42000 |
4 | 0 | m | m | s | d | 41000 | segment3 | segment3 | 42000 |
2 | 0 | p | p | c | u | 40000 | segment1 | segment1 | 43000 |
(5 rows)
6.执行全量恢复
[gpadmin@master~]$
gprecoverseg -F
成功没有报错之后，gpstate -m查看状态
20160802:15:17:53:032633 gpstate:master:gpadmin-[INFO]:--------------------------------------------------------------
20160802:15:17:53:032633 gpstate:master:gpadmin-[INFO]:- Mirror Datadir Port Status Data Status
20160802:15:17:53:032633 gpstate:master:gpadmin-[INFO]:-
segment3 /data/mirror/gpseg0 41000 Passive Resynchronizing
20160802:15:17:53:032633 gpstate:master:gpadmin-[INFO]:- segment1 /data/mirror/gpseg1 41000 Passive Synchronized
20160802:15:17:53:032633 gpstate:master:gpadmin-[INFO]:--------------------------------------------------------------
============================================================================================
20160802:15:18:31:032685 gpstate:master:gpadmin-[INFO]:--------------------------------------------------------------
20160802:15:18:31:032685 gpstate:master:gpadmin-[INFO]:- Mirror Datadir Port Status Data Status
20160802:15:18:31:032685 gpstate:master:gpadmin-[INFO]:-
segment3 /data/mirror/gpseg0 41000 Passive Synchronized
20160802:15:18:31:032685 gpstate:master:gpadmin-[INFO]:- segment1 /data/mirror/gpseg1 41000 Passive Synchronized
20160802:15:18:31:032685 gpstate:master:gpadmin-[INFO]:--------------------------------------------------------------
7.关闭数据库
并将原segment2中gpseg0的文件重新另命名，再次启动数据库成功，删除该节点，数据节点迁移成功完毕。
8.改写配置文件
segment3:segment3:40001:/data/primary/gpseg2:6:2:p:43001
segment2:segment2:41001:/data/mirror/gpseg2:7:2:m:42001
9.执行gpexpand -i 添加节点
没有报错，查看状态
20160803:09:28:28:036223 gpstate:master:gpadmin-[INFO]:--------------------------------------------------------------
20160803:09:28:28:036223 gpstate:master:gpadmin-[INFO]:- Mirror Datadir Port Status Data Status
20160803:09:28:28:036223 gpstate:master:gpadmin-[INFO]:- segment3 /data/mirror/gpseg0 41000 Passive
Synchronized
20160803:09:28:28:036223 gpstate:master:gpadmin-[INFO]:- segment1 /data/mirror/gpseg1 41000 Passive
Synchronized
20160803:09:28:28:036223 gpstate:master:gpadmin-[INFO]:- segment2 /data/mirror/gpseg2 41001 Passive
Synchronized
20160803:09:28:28:036223 gpstate:master:gpadmin-[INFO]:--------------------------------------------------------------
x=# select gp_segment_id,count(1) from tab_x1 group by 1 order by 1;
gp_segment_id | count
---------------+-------
0 | 36550
1 | 26119
(2 rows)
10.开始进行表重分布（60h是执行周期）
xx=# select gp_segment_id,count(1) from tab_x1 group by 1 order by 1;
gp_segment_id | count
---------------+-------
0 | 20896
1 | 20878
2 | 20895
(3 rows)
11.在gpexpand -i 的时候，多了个gpexpand的schema
[gpadmin@master ~]$ gpexpand -c --移除gpexpand schema
Do you want to dump thegpexpand.status_detail table to file? Yy|Nn (default=Y):
> y
