corosync+ pacemaker实现pg流复制自动切换（二）

Postgre SQL 前端之家
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五、测试

5.1备节点失效

在node2上杀死postgres数据库进程，模拟备节点上数据库崩溃：

[root@node2~]#killall-9postgres



查看此时集群状态：

[root@node1~]#crm_mon-Afr-1
Lastupdated:WedJan2202:15:062014
Lastchange:WedJan2202:15:332014viacrm_attributeonnode1
Stack:classicopenais(withplugin)
CurrentDC:node1-partitionwithquorum
Version:1.1.10-14.el6_5.2-368c726
2Nodesconfigured,2expectedvotes
7Resourcesconfigured


Online:[node1node2]

Fulllistofresources:

vip-slave(ocf::heartbeat:IPaddr2):Startednode1
ResourceGroup:master-group
vip-master(ocf::heartbeat:IPaddr2):Startednode1
vip-rep(ocf::heartbeat:IPaddr2):Startednode1
Master/SlaveSet:msPostgresql[pgsql]
Masters:[node1]
Stopped:[node2]
CloneSet:clnPingCheck[pingCheck]
Started:[node1node2]

NodeAttributes:
*Nodenode1:
+default_ping_set:100
+master-pgsql:1000
+pgsql-data-status:LATEST
+pgsql-master-baseline:0000000006000078
+pgsql-status:PRI
*Nodenode2:
+default_ping_set:100
+master-pgsql:-INFINITY
+pgsql-data-status:DISCONNECT
+pgsql-status:STOP

Migrationsummary:
*Nodenode2:
pgsql:migration-threshold=1fail-count=1last-failure='WedJan2202:15:352014'
*Nodenode1:

Failedactions:
pgsql_monitor_7000onnode2'notrunning'(7):call=42,status=complete,last-rc-change='WedJan2202:14:582014',queued=0ms,exec=0ms

{vip-slave资源已成功切换到了node1上}

重启node2上的corosync，数据库将重新伴随启动：

[root@node2~]#servicecorosyncrestart
[root@node1~]#crm_mon-Afr-1
Lastupdated:WedJan2202:16:242014
Lastchange:WedJan2202:16:552014viacrm_attributeonnode1
Stack:classicopenais(withplugin)
CurrentDC:node1-partitionwithquorum
Version:1.1.10-14.el6_5.2-368c726
2Nodesconfigured,2expectedvotes
7Resourcesconfigured


Online:[node1node2]

Fulllistofresources:

vip-slave(ocf::heartbeat:IPaddr2):Startednode2
ResourceGroup:master-group
vip-master(ocf::heartbeat:IPaddr2):Startednode1
vip-rep(ocf::heartbeat:IPaddr2):Startednode1
Master/SlaveSet:msPostgresql[pgsql]
Masters:[node1]
Slaves:[node2]
CloneSet:clnPingCheck[pingCheck]
Started:[node1node2]

NodeAttributes:
*Nodenode1:
+default_ping_set:100
+master-pgsql:1000
+pgsql-data-status:LATEST
+pgsql-master-baseline:0000000006000078
+pgsql-status:PRI
*Nodenode2:
+default_ping_set:100
+master-pgsql:100
+pgsql-data-status:STREAMING|SYNC
+pgsql-status:HS:sync

Migrationsummary:
*Nodenode2:
*Nodenode1:

{vip-slave又重新回到了nod2上}

5.2主节点失效切换

在node1上杀死postgres数据库进程，模拟主节点上数据库崩溃：

[root@node1~]#killall-9postgres


等会查看集群状态：

[root@node2~]#crm_mon-Afr-1
Lastupdated:WedJan2202:17:502014
Lastchange:WedJan2202:18:162014viacrm_attributeonnode2
Stack:classicopenais(withplugin)
CurrentDC:node1-partitionwithquorum
Version:1.1.10-14.el6_5.2-368c726
2Nodesconfigured,2expectedvotes
7Resourcesconfigured


Online:[node1node2]

Fulllistofresources:

vip-slave(ocf::heartbeat:IPaddr2):Startednode2
ResourceGroup:master-group
vip-master(ocf::heartbeat:IPaddr2):Startednode2
vip-rep(ocf::heartbeat:IPaddr2):Startednode2
Master/SlaveSet:msPostgresql[pgsql]
Masters:[node2]
Stopped:[node1]
CloneSet:clnPingCheck[pingCheck]
Started:[node1node2]

NodeAttributes:
*Nodenode1:
+default_ping_set:100
+master-pgsql:-INFINITY
+pgsql-data-status:DISCONNECT
+pgsql-status:STOP
*Nodenode2:
+default_ping_set:100
+master-pgsql:1000
+pgsql-data-status:LATEST
+pgsql-master-baseline:0000000008014A70
+pgsql-status:PRI

Migrationsummary:
*Nodenode2:
*Nodenode1:
pgsql:migration-threshold=1fail-count=1last-failure='WedJan2202:18:112014'

Failedactions:
pgsql_monitor_2000onnode1'notrunning'(7):call=2435,last-rc-change='WedJan2202:18:112014','宋体';font-size:13px;">{vip-master/vip-rep都已成功切换到node2上，且node2已变为master，node2上pg数据库状态已切换为PRI}
 

停止node1上的corosync：
 

[root@node1~]#servicecorosyncstop
 

执行一次基础同步：
 

[postgres@node1data]$pwd
/opt/pgsql/data
[postgres@node1data]$rm-rf*
[postgres@node1data]$pg_basebackup-h192.168.1.3-Upostgres-D/opt/pgsql/data/-P
19172/19172kB(100%),1/1tablespace
NOTICE:pg_stop_backupcomplete,allrequiredWALsegmentshavebeenarchived
[postgres@node1data]$ls
backup_labelbasepg_clogpg_ident.confpg_notifypg_stat_tmppg_tblspcPG_VERSIONpostgresql.conf
backup_label.oldglobalpg_hba.confpg_multixactpg_serialpg_subtranspg_twophasepg_xlogrecovery.done
 

启动node1上的corosync：
 

[root@node1~]#servicecorosyncstart
 

 

5.3主节点恢复
 

修复原主节点后将其恢复为当前备节点
 

在node1上执行一次基础同步：
 

[postgres@node1data]$pwd
/opt/pgsql/data
[postgres@node1data]$rm-rf*
[postgres@node1data]$pg_basebackup-h192.168.2.3-Upostgres-D/opt/pgsql/data/-P
19172/19172kB(100%),'宋体';font-size:13px;">启动heartbeat之前必须删除资锁，不然资源将不会伴随heartbeat启动：
 

[root@node1~]#rm-rf/var/lib/pgsql/tmp/PGsql.lock
 

{该锁文件在当节点为主节点时创建，但不会因为heartbeat的异常停止或数据库/系统的异常终止而自动删除，所以在恢复一个节点的时候只要该节点充当过主节点就需要手动清理该锁文件}
 

重启node1上的heartbeat：
 

[root@node1~]#serviceheartbeatrestart
 

过段时间后查看集群状态：
 

[root@node2~]#crm_mon-Afr1
============
Lastupdated:MonJan2708:50:432014
Stack:Heartbeat
CurrentDC:node2(f2dcd1df-7429-42f5-82e9-b73921f97cab)-partitionwithquorum
Version:1.0.12-unknown
2Nodesconfigured,unknownexpectedvotes
4Resourcesconfigured.
============

Online:[node1node2]

Fulllistofresources:

vip-slave(ocf::heartbeat:IPaddr2):Startednode1
ResourceGroup:master-group
vip-master(ocf::heartbeat:IPaddr2):Startednode2
vip-rep(ocf::heartbeat:IPaddr2):Startednode2
Master/SlaveSet:msPostgresql
Masters:[node2]
Slaves:[node1]
CloneSet:clnPingCheck
Started:[node1node2]

NodeAttributes:
*Nodenode1:
+default_ping_set:100
+master-pgsql:0:100
+pgsql-data-status:STREAMING|SYNC
+pgsql-status:HS:sync
*Nodenode2:
+default_ping_set:100
+master-pgsql:1:1000
+pgsql-data-status:LATEST
+pgsql-master-baseline:00000000120000B0
+pgsql-status:PRI

Migrationsummary:
*Nodenode1:
*Nodenode2:
 

{vip-slave已成功切到node1上，node1成功成为流复制备节点}
 

 

六、管理
 

6.1启动关闭corosync
 

[root@node1~]#servicecorosyncstart
[root@node1~]#servicecorosyncstop
 


 

6.2查看HA状态
 

[root@node1~]#crmstatus
Lastupdated:TueJan2123:55:132014
Lastchange:TueJan2123:37:362014viacrm_attributeonnode1
Stack:classicopenais(withplugin)
CurrentDC:node1-partitionwithquorum
Version:1.1.10-14.el6_5.2-368c726
2Nodesconfigured,2expectedvotes
7Resourcesconfigured


Online:[node1node2]

vip-slave(ocf::heartbeat:IPaddr2):Startednode2
ResourceGroup:master-group
vip-master(ocf::heartbeat:IPaddr2):Startednode1
vip-rep(ocf::heartbeat:IPaddr2):Startednode1
Master/SlaveSet:msPostgresql[pgsql]
Masters:[node1]
Slaves:[node2]
CloneSet:clnPingCheck[pingCheck]
Started:[node1node2]
 

6.3查看资源状态及节点属性 

[root@node1~]#crm_mon-Afr-1
Lastupdated:TueJan2123:37:202014
Lastchange:TueJan2123:37:362014viacrm_attributeonnode1
Stack:classicopenais(withplugin)
CurrentDC:node1-partitionwithquorum
Version:1.1.10-14.el6_5.2-368c726
2Nodesconfigured,'宋体';">6.4查看配置 

[root@node1~]#crmconfigureshow
nodenode1\
attributespgsql-data-status="LATEST"
nodenode2\
attributespgsql-data-status="STREAMING|SYNC"
primitivepgsqlocf:heartbeat:pgsql\
paramspgctl="/opt/pgsql/bin/pg_ctl"psql="/opt/pgsql/bin/psql"pgdata="/opt/pgsql/data/"start_opt="-p5432"rep_mode="sync"node_list="node1node2"restore_command="cp/opt/archivelog/%f%p"primary_conninfo_opt="keepalives_idle=60keepalives_interval=5keepalives_count=5"master_ip="192.168.1.3"stop_escalate="0"\
opstarttimeout="60s"interval="0s"on-fail="restart"\
opmonitortimeout="60s"interval="7s"on-fail="restart"\
opmonitortimeout="60s"interval="2s"on-fail="restart"role="Master"\
oppromotetimeout="60s"interval="0s"on-fail="restart"\
opdemotetimeout="60s"interval="0s"on-fail="stop"\
……
……
 

6.5实时监控HA 

[root@node1~]#crm_mon-Afr
Lastupdated:WedJan2200:40:122014
Lastchange:TueJan2123:37:362014viacrm_attributeonnode1
Stack:classicopenais(withplugin)
CurrentDC:node1-partitionwithquorum
Version:1.1.10-14.el6_5.2-368c726
2Nodesconfigured,2expectedvotes
7Resourcesconfigured


Online:[node1node2]

Fulllistofresources:

vip-slave(ocf::heartbeat:IPaddr2):Startednode2
ResourceGroup:master-group
vip-master(ocf::heartbeat:IPaddr2):Startednode1
vip-rep(ocf::heartbeat:IPaddr2):Startednode1
Master/SlaveSet:msPostgresql[pgsql]
Masters:[node1]
Slaves:[node2]
CloneSet:clnPingCheck[pingCheck]
Started:[node1node2]

NodeAttributes:
*Nodenode1:
+default_ping_set:100
+master-pgsql:1000
+pgsql-data-status:LATEST
+pgsql-master-baseline:0000000006000078
+pgsql-status:PRI
*Nodenode2:
+default_ping_set:100
+master-pgsql:100
+pgsql-data-status:STREAMING|SYNC
+pgsql-status:HS:sync

Migrationsummary:*Nodenode2:*Nodenode1:
 

6.6 crm_resource命令 

资源启动/关闭：
 

[root@node1~]#crm_resource-rvip-master-vstarted
[root@node1~]#crm_resource-rvip-master-vstoped
 


 

列举资源：
 

[root@node1~]#crm_resource-L
vip-slave(ocf::heartbeat:IPaddr2):Started
ResourceGroup:master-group
vip-master(ocf::heartbeat:IPaddr2):Started
vip-rep(ocf::heartbeat:IPaddr2):Started
Master/SlaveSet:msPostgresql[pgsql]
Masters:[node1]
Slaves:[node2]
CloneSet:clnPingCheck[pingCheck]
Started:[node1node2]
 

查看资源位置： 

[root@node1~]#crm_resource-W-rpgsql
resourcepgsqlisrunningon:node2
 

迁移资源： 

[root@node1~]#crm_resource-M-rvip-slave-Nnode2
 

删除资源： 

[root@node1~]#crm_resource-D-rvip-slave-tprimitive
 

6.7 crm命令 

列举指定的RA：
 

[root@node1~]#crmralistocfpacemaker
ClusterMonDummyHealthcpuHealthSMARTStatefulSysInfoSystemHealthcontroldpingpingd
remote
 

删除节点： 

[root@node1~]#crmnodedeletenode2
 

停用节点： 

[root@node1~]#crmnodestandbynode2
 

启用节点： 

[root@node1~]#crmnodeonlinenode2
 

配置pacemaker： 

[root@node1~]#crmconfigure
crm(live)configure#
……
……
crm(live)configure#commit
crm(live)configure#quit
 

6.8重置failcount 

[root@node1~]#crmresource
crm(live)resource#failcountpgsqlsetnode10
crm(live)resource#failcountpgsqlshownode1
scope=statusname=fail-count-pgsqlvalue=0


[root@node1~]#crmresourcecleanuppgsql
Cleaninguppgsql:0onnode1
Waitingfor1repliesfromtheCRMd.OK


[root@node1~]#crm_failcount-G-Unode1-rpgsql
scope=statusname=fail-count-pgsqlvalue=INFINITY
[root@node1~]#crm_failcount-D-Unode1-rpgsql
 


 

七、问题记录
 

7.1 Q1
 

问题现象：
 

corosync.log日志中报错：
 

Jan 15 10:23:57 node1 lrmd: [6327]: info: RA output: (pgsql:0:monitor:stderr) /usr/lib/ocf/resource.d//heartbeat/pgsql: line 1749: ocf_local_nodename: command not found
 

Jan 15 10:23:57 node1 crm_attribute: [11094]: info: Invoked: /usr/sbin/crm_attribute -l reboot -N -n -v 0000000006000090 pgsql-xlog-loclrm_get_rsc_type_Metadata(578)
 

Jan 15 10:23:57 node1 lrmd: [6327]: info: RA output: (pgsql:0:monitor:stderr) Could not map uname=-n to a UUID: The object/attribute does not exist
 

解决方式：
 

查看pgsql脚本，发现其中使用了ocf_local_nodename，该函数本该在ocf-shellfuncs.in中有定义，但却没有这个函数，上网查看相关论坛
 

http://www.gossamer-threads.com/lists/linuxha/users/89379?do=post_view_threaded
 

指出此时需要相关补丁，解决ocf_local_nodename函数的补丁：
 

https://github.com/ClusterLabs/resource-agents/commit/abc1c3f6464f6e5e7a1e41cd7c9b8179896c1903
 

最新的版本没有ocf_local_nodename函数，所以使用以下版本：
 

{注：确保pacemaker版本>1.1.8，不然crm_node -n命令无法使用}
 

https://github.com/ClusterLabs/resource-agents/blob/a6f4ddf76cb4bbc1b3df4c9b6632a6351b63c19e/heartbeat/pgsql
 

https://github.com/ClusterLabs/resource-agents/tree/abc1c3f6464f6e5e7a1e41cd7c9b8179896c1903/heartbeat
 

不含有ocf_local_nodename函数的pgsql脚本：
 

https://raw.github.com/ClusterLabs/resource-agents/a6f4ddf76cb4bbc1b3df4c9b6632a6351b63c19e/heartbeat/pgsql
 

7.2 Q2
 

问题现象：
 

[root@node1~]#crmconfigureloadupdatepgsql.crm
WARNING:pingCheck:specifiedtimeout60sforstartissmallerthantheadvised90
WARNING:pingCheck:specifiedtimeout60sforstopissmallerthantheadvised100
WARNING:pgsql:specifiedtimeout60sforstopissmallerthantheadvised120
WARNING:pgsql:specifiedtimeout60sforstartissmallerthantheadvised120
WARNING:pgsql:specifiedtimeout60sfornotifyissmallerthantheadvised90
WARNING:pgsql:specifiedtimeout60sfordemoteissmallerthantheadvised120
WARNING:pgsql:specifiedtimeout60sforpromoteissmallerthantheadvised120
ERROR:master-group:attributeordereddoesnotexist
Doyoustillwanttocommit?no
 

错误提示：在定义的master-group中ordered属性不存在
 

（1）该问题是pacemaker版本所致，在pacemaker-1.1版本中不支持ordered,colocated属性，通过以下方法以1.0版本的cibconfig.py替换当前新版本试图解决此问题，结果失败：
 

[root@node1~]#vim/usr/lib64/python2.6/site-packages/crmsh/cibconfig.py
[root@node1~]#cd/usr/lib64/python2.6/site-packages/crmsh/
[root@node1crmsh]#mvcibconfig.pycibconfig.py.bak
[root@node1crmsh]#wgethttps://github.com/ClusterLabs/pacemaker-1.0/blob/fa1a99ab36e0ed015f1bcbbb28f7db962a9d1abc/shell/modules/cibconfig.py
 

（2）从配置脚本中去除关于ordered的定义（成功）：
 

group master-group \
 

 vip-master\
 

 vip-rep\
 

 Meta\
 

 ordered="false"
 

改为：
 

 vip-rep
 

7.3 Q3
 

安装pacemaker时报错：
 

#yuminstallpacemaker*
……
-->ProcessingDependency:libesmtp.so.5()(64bit)forpackage:pacemaker
-->FinishedDependencyResolution
pacemaker-1.0.12-1.el5.centos.i386fromclusterlabshasdepsolvingproblems
-->MissingDependency:libesmtp.so.5isneededbypackagepacemaker-1.0.12-1.el5.centos.i386(clusterlabs)
pacemaker-1.0.12-1.el5.centos.x86_64fromclusterlabshasdepsolvingproblems
-->MissingDependency:libesmtp.so.5()(64bit)isneededbypackagepacemaker-1.0.12-1.el5.centos.x86_64(clusterlabs)
Error:MissingDependency:libesmtp.so.5isneededbypackagepacemaker-1.0.12-1.el5.centos.i386(clusterlabs)
Error:MissingDependency:libesmtp.so.5()(64bit)isneededbypackagepacemaker-1.0.12-1.el5.centos.x86_64(clusterlabs)
Youcouldtryusing--skip-brokentoworkaroundtheproblem
Youcouldtryrunning:package-cleanup--problems
package-cleanup--dupes
rpm-Va--nofiles--nodigest
Theprogrampackage-cleanupisfoundintheyum-utilspackage.
 

提示缺少libesmtp，安装即可
 

#wgetftp://ftp.univie.ac.at/systems/linux/fedora/epel/5/x86_64/libesmtp-1.0.4-5.el5.x86_64.rpm
#wgetftp://ftp.univie.ac.at/systems/linux/fedora/epel/5/i386/libesmtp-1.0.4-5.el5.i386.rpm
#rpm-ivhlibesmtp-1.0.4-5.el5.x86_64.rpm
#rpm-ivhlibesmtp-1.0.4-5.el5.i386.rpm
 

7.4 Q4 

加载crm配置时报错：
 

[root@node1~]#crmconfigureloadupdatepgsql.crm
ERROR:pgsql:parameterrep_modedoesnotexist
ERROR:pgsql:parameternode_listdoesnotexist
ERROR:pgsql:parametermaster_ipdoesnotexist
ERROR:pgsql:parameterrestore_commanddoesnotexist
ERROR:pgsql:parameterprimary_conninfo_optdoesnotexist
WARNING:pgsql:specifiedtimeout60sforstopissmallerthantheadvised120
WARNING:pgsql:actionmonitor_MasternotadvertisedinMeta-data,itmaynotbesupportedbytheRA
WARNING:pgsql:specifiedtimeout60sforstartissmallerthantheadvised120
WARNING:pgsql:actionnotifynotadvertisedinMeta-data,itmaynotbesupportedbytheRA
WARNING:pgsql:actiondemotenotadvertisedinMeta-data,itmaynotbesupportedbytheRA
WARNING:pgsql:actionpromotenotadvertisedinMeta-data,itmaynotbesupportedbytheRA
WARNING:pingCheck:specifiedtimeout60sforstartissmallerthantheadvised90
WARNING:pingCheck:specifiedtimeout60sforstopissmallerthantheadvised100
Doyoustillwanttocommit?no
 

参数不存在是因为pgsql脚本太旧，需要替换
 

 

scppgsqlroot@192.168.100.201:/usr/lib/ocf/resource.d/heartbeat/
scpocf-shellfuncs.inroot@192.168.100.201:/usr/lib/ocf/lib/heartbeat/

scppgsqlroot@192.168.100.202:/usr/lib/ocf/resource.d/heartbeat/
scpocf-shellfuncs.inroot@192.168.100.202:/usr/lib/ocf/lib/heartbeat/
 


 

7.5 Q5
 

[root@node1~]#crm_mon-Afr-1
Lastupdated:TueJan2105:10:562014
Lastchange:TueJan2105:10:082014viacibadminonnode1
Stack:classicopenais(withplugin)
CurrentDC:node1-partitionwithquorum
Version:1.1.10-14.el6_5.2-368c726
2Nodesconfigured,2expectedvotes
7Resourcesconfigured


Online:[node1node2]

Fulllistofresources:

vip-slave(ocf::heartbeat:IPaddr2):Stopped
ResourceGroup:master-group
vip-master(ocf::heartbeat:IPaddr2):Stopped
vip-rep(ocf::heartbeat:IPaddr2):Stopped
Master/SlaveSet:msPostgresql[pgsql]
Stopped:[node1node2]
CloneSet:clnPingCheck[pingCheck]
Stopped:[node1node2]

NodeAttributes:
*Nodenode1:
*Nodenode2:

Migrationsummary:
*Nodenode1:
*Nodenode2:

Failedactions:
pingCheck_monitor_0onnode1'invalidparameter'(2):call=23,last-rc-change='TueJan2105:10:102014',queued=200ms,exec=0ms
pingCheck_monitor_0onnode2'invalidparameter'(2):call=23,last-rc-change='TueJan2105:09:362014',queued=281ms,'宋体';font-size:13px;">该错误是因为脚本定义中的pingCheck调用的pingd脚本中存在未知参数，经查ocf/pacemaker/pingd中不存在multiplier参数：
 

primitive pingCheck ocf:pacemaker:pingd \
 

 params\
 

 name="default_ping_set"\
 

 host_list="192.168.100.1"\
 

 multiplier="100"\
 

 opstart timeout="60s" interval="0s" on-fail="restart" \
 

 opmonitor timeout="60s" interval="10s" on-fail="restart" \
 

 opstop timeout="60s" interval="0s" on-fail="ignore"
 

因此将调用改为ocf:heartbeat:pingd
 

7.6 Q6
 

corosync日志中报错：
 

Jan 21 04:36:02 corosync [TOTEM ] Received message has invalid digest... ignoring.
 

Jan 21 04:36:02 corosync [TOTEM ] Invalid packet data
 

说明网络中存在相同的多播，更改多播地址即可。
 

八、参考资源
 

脚本：
 

https://github.com/ClusterLabs/resource-agents/blob/master/heartbeat/pgsql
 

脚本使用说明：
 

https://github.com/t-matsuo/resource-agents/wiki/Resource-Agent-for-Postgresql-9.1-streaming-replication
 

crm_resouce命令：
 

http://www.novell.com/zh-cn/documentation/sle_ha/book_sleha/data/man_crmresource.html
 

crm_failcount命令：
 

http://www.novell.com/zh-cn/documentation/sle_ha/book_sleha/data/man_crmfailcount.html

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