咨询rac上em问题

lxhbww

咨询下rac上em是不是只有在一节点上才能正常
现象启动节点一em，访问em正常 关闭再启动节点二em显示的也是节点一的，但无法访问
节点一节点二em都开，访问em正常，节点一出故障重启则em又不能用了
是哪配置有问题么？还是rac中em就是只能开节点一才有效？

Maclean Liu(刘相兵

没有版本 没有日志 没有报错信息  请重构你的问题

gdpr-dba

我也想知道答案，我来帮lz描述吧：
假如rac有两个节点node1和node2，配置了em，但是只能用https://node1:1158/em访问，无法用https://node2:1158/em来访问，同时在node1和node2上执行emctl status dbconsole的结果都是https://node1:1158/em，所以问题是为什么只有一个节点能配置em?

shunzi

这个问题，我认为是你在那个节点上装的就用哪个节点来访问，不过装的时候选的是集群模式，你可以监控所有节点罢了。我也遇到过这种情况。没必要纠结这个问题啊。

lxhbww

能不纠结嘛，因为如果在第一节点安装的，到时节点一出问题了，数据库能正常，因为有节点2，但em就不行了，因为只有节点一em启来才行，节点二启的em不能用。所以想请教是不是有哪位专家怎么配置就可以哪个节点启em都能进行监控。就像数据库一样，不管哪节点出问题都不受大的影响，最少还有个节点正常，而像我说的节点二出问题没事，节点一有数据库，且em也正常，但如果节点一出问题则有数据库，但没em了啊。

Maclean Liu(刘相兵

ODM FINDING:


Enterprise Manager Database Control only starts on one node of my RAC cluster. How do I start it on another node?


Applies to:
Enterprise Manager for Oracle Database - Version: 10.2.0.1 and later   [Release: 10.2 and later ]
Information in this document applies to any platform.
***Checked for relevance on 02-Apr-2012***
Goal
Enterprise Manager Database Control only starts on one node of my RAC cluster. How do I start it on another node?
Solution

By default, the Database Control Console will only start on the local node. On every other node of the cluster, only the Enterprise Manager agent will start. This is a tuning measure incorporated in the design of Database Control version 10.2.x because the Database Control Console opens a number of connections to the database - starting only one console limits these connections.

On every other node, the commands emctl start dbconsole and emctl stop dbconsole only  start and stop the agent. Each of the remote agents will upload their respective data to  the console running on the local node.

The following command reconfigures the  current Database Control setup. The action of the command is also mention below.

emca -reconfig dbcontrol –cluster –EM_NODE <nodename> -EM_SID_LIST <SID list>
    where <nodename> is the RAC cluster name of a host and <SID list> is a comma-separated list of database system     identifiers.

    1. Starts a Database Control Console on <nodename>, if none has been started
    2. Redirects the agents monitoring the database instances in <SID list> so that they
    upload their data to the console running on <nodename>. Also, agents monitoring
    database instances on <nodename> will also upload their data to the local console. Note that if
    you do not pass -EM_NODE or -EM_SID_LIST at the command line, you will be prompted for them.
    -EM_NODE defaults to the local host if not specified when prompted. -EM_SID_LIST defaults to all
    database instances if not specified.

So, because the way in which it was designed, the dbconsole could not run on several nodes serving the same instances in the same time.

Maclean Liu(刘相兵

because the way in which it was designed, the dbconsole could not run on several nodes serving the same instances in the same time.


由于设计上的原因， dbconsole (or db control ) 在RAC 中无法同时运行在多个节点上， 而只能运行在一个节点上。

但是可以通过 以下命令 将dbconsole 转移到该节点。

emca -reconfig dbcontrol –cluster –EM_NODE <nodename> -EM_SID_LIST <SID list>

am196

emca -reconfig dbcontrol –cluster –EM_NODE <nodename> -EM_SID_LIST <SID list>
转换一下要花我少时间呀？

shinee

对的，是这个样子的。在RAC模式下配置OEM的时候可以选择在一个主节点配置，这样其他的节点都是通过这一个OEM进行管理的，例如：
假如rac有两个节点node1和node2，配置了em，但是只能用https://node1:1158/em访问，无法用https://node2:1158/em来访问，同时在node1和node2上执行emctl status dbconsole的结果都是https://node1:1158/em
通过 https://node1:1158/em 来实现整个RAC节点的管理，这个是oracle 设计的问题.