[Beowulf] KVM to a compute node - ssh

[Michael Will]

On Thursday 03 June 2004 10:59 am, Robert G. Brown wrote:
> On Thu, 3 Jun 2004, Michael Will wrote:
> > This is a component we put into our products, rather than a standalone
> > product.
> >
> > If you look at a 1U opteron system for example, you can add it for $21 in
> > the "additional network interface" section.
> >
> > http://www.penguincomputing.com/products/servers/altus1000E.php
>
> No kidding!  Gee, I missed this when ordering my stack of 1000Es.  I
> suppose that it is an Altus-specific product, then.  

Both the relion and the altus line have it. But it definitely is penguin 
specific at this point.

> And curiously 
> enough, it is two Penguin 1000Es of mine that are stuck right now and it
> was them that I tried to reboot with Don Becker's WOL tool (and failed).
I don't have any experience with WOL but I will ask Don the next time I see 
him ;-)

> Any hints on rebooting a hung opteron via WOL and the network?  Can a
> 1000E be configured so that this will work, or will WOL only work to
> turn one on if they are off?
The latter is what I assume.

> You see, a 32 port terminal server and the $21 interface and the cable
> per node cost more than $100 per node to be able to remotely power cycle
> it.  That is more than the cost of an extra 1000E itself.  We'd much
> rather buy an extra 1000E than buy the TS and interface (especially
> since we'd have to buy three or four TS's to cover all our nodes, which
> starts to look like real money even if a mere $3K doesn't), but we'd
> really like to have this cake and eat it too -- still be able to
> remotely bounce the nodes -- and not have yet another box that can break
> and that eats resources.  In the meantime, $3200 also pays for a lot of
> walks downstairs, regardless of the inconvenience.

1. If you are only purchasing the console server for the remote control 
capability, then it does add $100 per node.  But then you get a serial 
console "for free".  Frequently, people want the serial console 
functionality as well and for them, the remote control is "almost free" 
since they would have paid for the TS anyway.

2. It is possible to connect two systems with remote control cards with 
a cross-over cable.  In this way system A can reboot and power cycle 
system B and system B can do likewise to A.  Or you could connect the 
systems in a chain A->B->C->D->E using both serial ports on each machine.

> If the server room were the other side of campus (and hence cost thirty
> plus minutes of time to walk over and reboot instead of five), things
> might be different, but in all economic decisions there are crossover
> points where it isn't worth it to buy something that is really pretty
> expensive just for the convenience.
Never understimate the cost of having a technician come in instead of dial in.

Michael
-- 
Michael Will, Linux Sales Engineer
NEWS: We have moved to a larger iceberg :-)
NEWS: 300 California St., San Francisco, CA.
Tel:  415-954-2822  Toll Free:  888-PENGUIN
Fax:  415-954-2899 
www.penguincomputing.com