*Locators* have the GemFire System property "jmx-manager" set to **true**
by default.  When a JMX client (such as *Gfsh*) contacts a *Locator* asking
who the "*Manager*" of the GemFire cluster is, the *Locator* will respond
by searching the cluster for a *Manager*.  If found, the coordinates
(IP/Port) of the *Manager* are returned to the client that initiated the
request.  If a *Manager* does not currently exist in the cluster, the
*Locator* will then serve as the *Manager*.

It is possible that another member (*Locator* or *Server*) has elected to
serve as a *Manager* too, with jmx-manager=true.  The member can even be
forced to start up as a *Manager* with jmx-manager-start=true.

However, if the *Locator* from our first scenario above goes down, there is
no "automatic failover" where another member (with jmx-manager=true, but
*not* jmx-manager-start=true) in the cluster picks up the tab and becomes
the new *Manager* for the cluster.  It would require a client to connect to
that member asking for a *Manager* to trigger the Management Service in
that member to start.

See the GF UG for more details...
http://gemfire.docs.pivotal.io/latest/userguide/index.html#managing/management/jmx_manager_operations.html

Note, you can connect any JMX client (e.g. JConsole or JVisualVM) to any
GemFire member in the cluster at any time.  Each GemFire member JVM process
always has an instance of the MBeanServer running that enables a tool like
JConsole to connect to it.  However, since the member may not be a Manager
for the cluster, you will not see a "federated" view of the entire cluster.

-John



On Thu, Jul 23, 2015 at 8:17 AM, Gregory Green <[email protected]> wrote:

> Hello Everyone,
>
>
> Is there a way for a secondary locator to automatically start acting as a
> JMX manager if the primary locator/jmx manager is killed?
>
>
> It appears that I need to either make both of the locators jmx managers at
> start up by adding
>
> jmx-manager-start=true to the  locator gemfire.properties
>
>
> Or restart the secondary locator when the primary locator goes down.
>
>


-- 
-John
503-504-8657
john.blum10101 (skype)

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