what are the thoughts on running a hadoop cluster in a datacenter with
respect to power? should all the boxes have redundant power supplies and be
on dual power? or just dual power for the namenode, secondary namenode, and
hbase master, and then perhaps switch the power source per rack for the
slaves to provide resilience to a power failure? or even just run
everything on single power and accept the risk that everything can do down
at once?

NN, SN and JT must have separated power adapter, for the entire cluster are dual adapter recommend.
For HBase and zookeeper servers / regionservers also dual adapters with seperated power lines recommend.

- Alex

sent via my mobile device

On Jan 7, 2012, at 11:23 AM, Koert Kuipers <[EMAIL PROTECTED]> wrote:

> what are the thoughts on running a hadoop cluster in a datacenter with
> respect to power? should all the boxes have redundant power supplies and be
> on dual power? or just dual power for the namenode, secondary namenode, and
> hbase master, and then perhaps switch the power source per rack for the
> slaves to provide resilience to a power failure? or even just run
> everything on single power and accept the risk that everything can do down
> at once?

Be aware that if half of your cluster goes down, depending of the version and configuration of Hadoop, there may be a replication storm, as hadoop tries to bring it all back up to the proper number of replications.  Your cluster may still be unusable in this case.

--Bobby Evans

On 1/7/12 2:55 PM, "Alexander Lorenz" <[EMAIL PROTECTED]> wrote:

NN, SN and JT must have separated power adapter, for the entire cluster are dual adapter recommend.
For HBase and zookeeper servers / regionservers also dual adapters with seperated power lines recommend.

- Alex

sent via my mobile device

On Jan 7, 2012, at 11:23 AM, Koert Kuipers <[EMAIL PROTECTED]> wrote:

> what are the thoughts on running a hadoop cluster in a datacenter with
> respect to power? should all the boxes have redundant power supplies and be
> on dual power? or just dual power for the namenode, secondary namenode, and
> hbase master, and then perhaps switch the power source per rack for the
> slaves to provide resilience to a power failure? or even just run
> everything on single power and accept the risk that everything can do down
> at once?

If you configure your replica number as 3 or more. I would suggest you keep
half of your nodes with dual power on each rack, especially node with
larger or more disks. As well as your namenode, resource manager,
secondaryNamenode, and all other master nodes.

On Mon, Jan 9, 2012 at 10:50 AM, Robert Evans <[EMAIL PROTECTED]> wrote:

> Be aware that if half of your cluster goes down, depending of the version
> and configuration of Hadoop, there may be a replication storm, as hadoop
> tries to bring it all back up to the proper number of replications.  Your
> cluster may still be unusable in this case.
>
> --Bobby Evans
>
> On 1/7/12 2:55 PM, "Alexander Lorenz" <[EMAIL PROTECTED]> wrote:
>
> NN, SN and JT must have separated power adapter, for the entire cluster
> are dual adapter recommend.
> For HBase and zookeeper servers / regionservers also dual adapters with
> seperated power lines recommend.
>
> - Alex
>
> sent via my mobile device
>
> On Jan 7, 2012, at 11:23 AM, Koert Kuipers <[EMAIL PROTECTED]> wrote:
>
> > what are the thoughts on running a hadoop cluster in a datacenter with
> > respect to power? should all the boxes have redundant power supplies and
> be
> > on dual power? or just dual power for the namenode, secondary namenode,
> and
> > hbase master, and then perhaps switch the power source per rack for the
> > slaves to provide resilience to a power failure? or even just run
> > everything on single power and accept the risk that everything can do
> down
> > at once?
>
>