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Greenplum和Deepgreen官方都没有给出删除节点的方法和建议,但实际上,我们可以对节点进行删除。由于不确定性,删除节点极有可能导致其他的问题,所以还行做好备份,谨慎而为。下面是具体的步骤:
1.查看数据库当前状态(12个实例)
[gpadmin@sdw1 ~]$ gpstate
20170816:12:53:25:097578 gpstate:sdw1:gpadmin-[INFO]:-Starting gpstate with args:
20170816:12:53:25:097578 gpstate:sdw1:gpadmin-[INFO]:-local Greenplum Version: 'postgres (Greenplum Database) 4.3.99.00 build Deepgreen DB'
20170816:12:53:25:097578 gpstate:sdw1:gpadmin-[INFO]:-master Greenplum Version: 'PostgreSQL 8.2.15 (Greenplum Database 4.3.99.00 build Deepgreen DB) on x86_64-unknown-linux-gnu, compiled by GCC gcc (GCC) 4.9.2 20150212 (Red Hat 4.9.2-6) compiled on Jul 6 2017 03:04:10'
20170816:12:53:25:097578 gpstate:sdw1:gpadmin-[INFO]:-Obtaining Segment details from master...
20170816:12:53:25:097578 gpstate:sdw1:gpadmin-[INFO]:-Gathering data from segments...
..
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:-Greenplum instance status summary
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:-----------------------------------------------------
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Master instance = Active
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Master standby = No master standby configured
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total segment instance count from metadata = 12
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:-----------------------------------------------------
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Primary Segment Status
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:-----------------------------------------------------
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total primary segments = 12
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total primary segment valid (at master) = 12
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total primary segment failures (at master) = 0
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total number of postmaster.pid files missing = 0
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total number of postmaster.pid files found = 12
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total number of postmaster.pid PIDs missing = 0
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total number of postmaster.pid PIDs found = 12
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total number of /tmp lock files missing = 0
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total number of /tmp lock files found = 12
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total number postmaster processes missing = 0
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Total number postmaster processes found = 12
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:-----------------------------------------------------
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Mirror Segment Status
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:-----------------------------------------------------
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:- Mirrors not configured on this array
20170816:12:53:27:097578 gpstate:sdw1:gpadmin-[INFO]:-----------------------------------------------------
2.并行备份数据库
使用 gpcrondump 命令备份数据库,这里不赘述,不明白的可以翻看文档。
3.关闭当前数据库
[gpadmin@sdw1 ~]$ gpstop -M fast
20170816:12:54:10:097793 gpstop:sdw1:gpadmin-[INFO]:-Starting gpstop with args: -M fast
20170816:12:54:10:097793 gpstop:sdw1:gpadmin-[INFO]:-Gathering information and validating the environment...
20170816:12:54:10:097793 gpstop:sdw1:gpadmin-[INFO]:-Obtaining Greenplum Master catalog information
20170816:12:54:10:097793 gpstop:sdw1:gpadmin-[INFO]:-Obtaining Segment details from master...
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:-Greenplum Version: 'postgres (Greenplum Database) 4.3.99.00 build Deepgreen DB'
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:---------------------------------------------
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:-Master instance parameters
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:---------------------------------------------
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- Master Greenplum instance process active PID = 31250
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- Database = template1
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- Master port = 5432
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- Master directory = /hgdata/master/hgdwseg-1
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- Shutdown mode = fast
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- Timeout = 120
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- Shutdown Master standby host = Off
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:---------------------------------------------
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:-Segment instances that will be shutdown:
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:---------------------------------------------
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- Host Datadir Port Status
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg0 25432 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg1 25433 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg2 25434 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg3 25435 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg4 25436 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg5 25437 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg6 25438 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg7 25439 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg8 25440 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg9 25441 u
20170816:12:54:11:097793 gpstop:sdw1:gpadmin-[INFO]:- sdw1 /hgdata/primary/hgdwseg10 25442 u