failovers

[sfaber]

I setup a remote database on a solaris machine with a mirror on a different solaris machine and a directory mirror on a PC all with remote connections and servers running. Then I connected to the directory mirror and was running OK to the primary. Then to test the failover I stopped the server to the primary but there was no failover and the ServerConsole just gave error messages about the connections and was unable to do anything,
even set the primary manually. I take it that autofailover doesn't really work, or it works only if the server is running on all machines. If that is the case then what is an auto failover?

[Gillmer J. Derge [TeamB]]

sfaber wrote:
> I take it that autofailover doesn't really work,

It works, but you need a certain number of working primary or readonly
mirrors even after the failure. I think it's at least 2 but maybe as
many as 3. In your case, after you killed one you only had one left
(the directory mirror doesn't count).

This is covered in the manual in the section on "The JDataStore High
Availability Server." Scan down to "The JDataStore engine and failover
/ Automatic failover." It begins, "When a primary mirror that is
configured with *two or more* [emphasis mine] automatic failover mirrors
fails ..."

So I think you need to add at least one more mirror to your test setup.

--
Gillmer J. Derge [TeamB]

[sfaber]

Thanks. When I first read you need 2 mirrors, I thought they were counting the primary, but there is a section on autofail that clearly states you need 2 readonly mirrors.

[Gillmer J. Derge [TeamB]]

FWIW, CodeGear's EventCentral site (http://ec.codegear.com) uses
JDataStore with 2 readonly mirrors for its database. When I initially
set it up, I tried to do some tests of the failover functionality, and I
never quite got it to work (for various reasons). However, it
definitely does actually work, because every now and then when I connect
to the database, I'll notice that the primary has moved to another server.