maas-devel team mailing list archive

[Jeffrey Lane <jeff@xxxxxxxxxxxxx>]

On Tue, Jan 21, 2014 at 12:01 AM, Julian Edwards
<julian.edwards@xxxxxxxxxxxxx> wrote:
> On 21/01/14 14:47, Jeffrey Lane wrote:
>> On Mon, Jan 20, 2014 at 9:20 PM, Julian Edwards
>> <julian.edwards@xxxxxxxxxxxxx> wrote:
>>> I am currently ripping out the notion of a "default" power type as it
>>> makes no sense.
>>>
>>> This raises a question:  if someone tries to start a node that has no
>>> power type set, should we:
>>>
>>>  * Raise an error?
>>>  * Set it allocated and wait for the user to turn it on manually?
>>>  * Have an explicit manual power type and do both of the above?
>>>
>>> Cheers.
>>
>> Do you mean by starting up a node that was manually added?  Or one
>> that was automatically enlisted?
>
> Either, it doesn't matter.
>
>> If a node is manually added, it makes sense to me to require a power
>> type be set explicitly.  If it's a node that's automatically enlisted,
>> shouldn't that be probe by the enlistment or commissioning tools?  At
>> that point, it seems MAAS should be able to determine if it's dealing
>> with a SeaMicro, an IPMI supporting BMC or a DMCI supporting BMC, for
>> example.
>
> The enlistment tools are not infallible though, and may fail to set a
> power type.

Right.  In my mind, thats an error condition and an error should be
raised in the UI.  Were I a voting member, I would still say default
to WOL in that case AND raise the error in case the tools didn't
successfully determine the type so the user can correct the data.  You
already mention that WOL is the default anyway, so does that mean the
only real change in the case of a failure to determine the power type
would be an error message?

>
>> I am, however, interested today in how MAAS handles automated
>> enlistment of a machine that only supports Wake-On-Lan.
>
> We don't want to support WoL really, it was originally only a hack to
> get simple setups working before we had IPMI working properly.

The reason this is in my mind currently is that as we move to 14.04
server certification, MAAS is required.  But what can I do with my
certification program to also address servers that do not contain BMCs
(low-end pizza boxes).  For example, my own SuperMicro at home does
not ship with BMC, that's an extra add-on.  (Hence my question about
WOL support as an aside).

>> Perhaps WOL should be the default in cases where the power type is not
>> successfully determined by enlistment or commissioning? (I would guess
>> enlistment would be the appropriate place in order to be able to
>> automatically turn the system on for commissioning).
>
> So WoL is the default now, but it's not a serious power type. It isn't
> able to power down, for instance.

Right  Shame there's not a magic Sleep-On-LAN packet too.  Tough call.
 ON the one hand you throw an error and possibly power up a system
that can't be powered down without manual intervention.  On the other
hand, something has to happen.

How about fire a warning, set to WOL AND not automatically start the
machine until the user accepts the warning.  Something like "We were
not able to determine the systems power type.  Please set the
appropriate type now or click THIS BUTTON to ignore this warning and
proceed to power on the system via Wake-On-LAN"/

I'm really not a fan of nag messages, but that seems like a good use
for one.  Still, grain of salt and all that.  You guys have a much
better idea of where you want this to go than I do, I'm just a
consumer and/or power-user in this case.
>
>> But take all that with a grain of salt from my limited experience with
>> MAAS.  So far, I've only really tried with a traditional IPMI BMC,
>> I've not yet tried via WOL or even using virsh on vms as I lack the
>> hardware to do either.
>
> Given that MAAS is basically useless unless it can turn power on and off
> (or at least boot on demand), a default power type is meaningless as
> it's not guaranteed to work unless configured properly.
>
> My original question still stands :)

Aye...  you should have seen our might MAAS cluster of Laptops... :)

Jeff