Open Stack

Hi,

I think I've found some bugs around host aggregates in the documentation, 
curious what people think.

The docs at 
"http://docs.openstack.org/trunk/config-reference/content/section_compute-scheduler.html#host-aggregates" 
contain this:


nova aggregate-create <name> <availability-zone>

     Create a new aggregate named <name> in availability zone 
<availability-zone>. Returns the ID of the newly created aggregate. Hosts can be 
made available to multiple availability zones, but administrators should be 
careful when adding the host to a different host aggregate within the same 
availability zone and pay attention when using the aggregate-set-metadata and 
aggregate-update commands to avoid user confusion when they boot instances in 
different availability zones. An error occurs if you cannot add a particular 
host to an aggregate zone for which it is not intended.



I'm pretty sure that there are multiple errors in there:

1) This command creates a new aggregate that is *exposed as* an availability 
zone.  It doesn't create a new aggregate within an availability zone. [1] 
Because of that the idea of a "different host aggregate within the same 
availability zone" doesn't make any sense.

2) Hosts can be part of multiple host aggregates, they cannot be part of 
multiple availability zones. [2]


Chris




References:
[1] 
http://blog.russellbryant.net/2013/05/21/availability-zones-and-host-aggregates-in-openstack-compute-nova/

[2] See the check in nova.compute.api.AggregateAPI._check_az_for_host()