Re: Clustering Software on CD

["jarkko teppo" <jht380%gmail.com@localhost>]

>
>>
>> Sun Cluster is good stuff.
>
> So what's Sun Cluster's approach to HA? I don't know it - technical
> details?
>

Light on technical details: http://www.sun.com/software/cluster/faq.xml
There's more technical stuff at blueprints.sun.com.

Basically it's a framework which you can use to build a HA and/or
scalable system for different applications from apache and bind to
oracle and other heavyweights.

Lots of nice features like global devices, global filesystem,
network failover, resource groups etc.etc...

Basically in a two node cluster might have:
-shared storage (needed in a two node cluster due to quorum, FC/scsi)
-NIC groups (done with IPMP, in.mpathd)
-Logical network addresses on top of IPMP groups which can then
 fail-over from nic-to-nic (or be scalable) or from host-to-host.
-Similar fail-over for storage and volumes.
-application agents (from Sun or DIY)

These resources are then gathered into resource groups and you
can specify different actions to do in case of resource or
resource group failure.

There are many nice details in there, for example split-brain
detection and admirable tendency of always failing (panicing)
(a) node(s) if data integrity is at risk.

It's quite flexible which makes explaining it pretty difficult:)

IPMP should be doable (SMOP), shared storage (not NFS) might be
a tad more difficult. Some people use firewire disks for that esp.
with Linux and Oracle 10g.. makes it possible to build a cheap
development rig.

I'm rambling and incoherent. Sorry,
-- 
jht