关于RAC 确定 master节点疑问

vmcd_gg

$cat $ORA_CRS_HOME/log/`hostname`/cssd/ocssd* |grep master
使用如下命令确定master节点出现下列信息：

[    CSSD]2011-12-10 22:27:37.744 [1252284736] >TRACE:   clssgmQueueGrockEvent: groupName(IGITEMALL) count(1) master(2) event(1), incarn 1, mbrc 1, to member 2, events 0x0, state 0x0
[    CSSD]2011-12-10 22:27:44.972 [1252284736] >TRACE:   clssgmQueueGrockEvent: groupName(DGITEM) count(2) master(1) event(1), incarn 2, mbrc 2, to member 1, events 0x0, state 0x0
[    CSSD]2011-12-10 22:27:50.271 [1252284736] >TRACE:   clssgmQueueGrockEvent: groupName(DBITEM) count(2) master(1) event(1), incarn 2, mbrc 2, to member 1, events 0x20, state 0x0
[    CSSD]2011-12-10 22:27:51.567 [1252284736] >TRACE:   clssgmAddMember: new master 0 for group(ORA_CLSRD_1_item)
[    CSSD]2011-12-10 22:27:55.806 [1252284736] >TRACE:   clssgmQueueGrockEvent: groupName(DG_DATA) count(4) master(0) event(1), incarn 60, mbrc 4, to member 1, events 0x0, state 0x0
[    CSSD]2011-12-10 22:28:00.717 [1252284736] >TRACE:   clssgmQueueGrockEvent: groupName(DG_ARCH) count(4) master(0) event(1), incarn 51, mbrc 4, to member 1, events 0x0, state 0x0
[    CSSD]2011-12-10 22:28:12.112 [1252284736] >TRACE:   clssgmQueueGrockEvent: groupName(IGITEMALL) count(2) master(2) event(1), incarn 2, mbrc 2, to member
2, events 0x0, state 0x0


其中 0 如果代表node 1 那么 2代表什么

这个系统一共有两个node

Maclean Liu(刘相兵

Some Metadata LOG


Node2 :

[root@vrh2 cssd]# cat ocssd.l01 |grep clssgmCMReconfig
2011-12-04 22:10:07.517: [    CSSD][1127934272]clssgmCMReconfig: reconfiguration successful, incarnation 216157713 with 1 nodes, local node number 2, master node number 2
2011-12-05 22:00:47.269: [    CSSD][1127532864]clssgmCMReconfig: reconfiguration successful, incarnation 216157715 with 1 nodes, local node number 2, master node number 2
2011-12-05 22:03:07.763: [    CSSD][1127532864]clssgmCMReconfig: reconfiguration successful, incarnation 216157716 with 2 nodes, local node number 2, master node number 2
2011-12-06 04:48:24.839: [    CSSD][1127721280]clssgmCMReconfig: noticed master(1) not supporting REPLAY, cleaning up grocks autonomously
2011-12-06 04:48:25.253: [    CSSD][1127721280]clssgmCMReconfig: reconfiguration successful, incarnation 216157718 with 2 nodes, local node number 2, master node number 1
2011-12-13 09:22:32.767: [    CSSD][1129257280]clssgmCMReconfig: noticed master(1) not supporting REPLAY, cleaning up grocks autonomously
2011-12-13 09:22:32.971: [    CSSD][1129257280]clssgmCMReconfig: reconfiguration successful, incarnation 216157721 with 2 nodes, local node number 2, master node number 1



Node 1:

[root@vrh1 cssd]# cat ocssd.l01 |grep clssgmCMReconfig
2011-12-13 09:22:33.200: [    CSSD][1130473792]clssgmCMReconfig: reconfiguration successful, incarnation 216157721 with 2 nodes, local node number 1, master node number 1
2011-12-18 06:34:31.890: [    CSSD][1130293568]clssgmCMReconfig: noticed master(2) not supporting REPLAY, cleaning up grocks autonomously
2011-12-18 06:34:31.932: [    CSSD][1130293568]clssgmCMReconfig: reconfiguration successful, incarnation 216157724 with 2 nodes, local node number 1, master node number 2
2011-12-19 21:40:22.468: [    CSSD][1128020288]clssgmCMReconfig: reconfiguration successful, incarnation 216157726 with 1 nodes, local node number 1, master node number 1



clssgmCMReconfig   ==> Group Management Cluster Master Reconfig  

这里可以看到 一号节点的  node number  一般是1
                        二号节点的  node number  一般是2

The CSS Daemon provides infrastructure

- Group Manager handles group and lock synchronization among nodes

- Node Monitor monitors other nodes

Group Management (clssgm.c and clssgm1.c) – Group Management (GM) manages group and lock services.  Once node serves as the GM master node.  All nodes serialize GM requests through the master node.  The master node broadcasts membership changes to all other nodes.  Group membership is synchronized at each cluster reconfiguration.  Each node interprets membership changes independently.

Client Services
===============

Group Services (clssgs.c) – CSS provides group services by notifying clients (such as lmon) of cluster membership information and changes.  When an instance joins the cluster it will join a group via GM.  When applications connect to CSS they join their group and all members of the group share some private data such as IPC endpoints.  The application will then use these IPC endpoints for communication.  There is also some public data accessible to non-group members.  The global data store (not persistent) is available for bootstrap and initial contact.  The oldest node or the node with the lowest number in the cluster is considered the source of this bitmap although the data is distributed for recovery reasons.

Group Services
Notifies clients of cluster membership information and changes
When an instance joins a cluster it will join a group [ via GM  ]
Existing members notified when new member becomes active in the cluster. E.g. a database instance.



When applications connect to CSS they join their group and all members of the group share some private data such as IPC endpoints.

[    CSSD]2011-12-10 22:27:37.744 [1252284736] >TRACE:   clssgmQueueGrockEvent: groupName(IGITEMALL) count(1) master(2) event(1), incarn 1, mbrc 1, to member 2, events 0x0, state 0x0




clssgmQueueGrockEvent Grock 队列事件，这里的master 2 指的不是 node number 而是 由 一系列 client process(如lmon)组成的group member.

vmcd_gg

great response  thanks

Maclean Liu(刘相兵

Grock is basically an internal structure to hold css group management informations.

Please check below
Master Note for Real Application Clusters (RAC) Oracle Clusterware and Oracle Grid Infrastructure [ID 1096952.1]
11gR2 Clusterware and Grid Home - What You Need to Know [ID 1053147.1]
http://download.oracle.com/docs/ ... 02/b14197/intro.htm

Please also see:
Oracle® Clusterware Administration and Deployment Guide 11g Release 2 (11.2)
http://download.oracle.com/docs/ ... 2/e10717/crsref.htm
http://www.dbspecialists.com/fil ... uick_reference.html