[openstack-dev] [nova] Looking for clarification on the diagnostics API

Matt Riedemann mriedem at us.ibm.com
Thu Oct 10 19:12:24 UTC 2013


Tempest recently got some new tests for the nova diagnostics API [1] which 
failed when I was running against the powervm driver since it doesn't 
implement that API.  I started looking at other drivers that did and found 
that libvirt, vmware and xenapi at least had code for the get_diagnostics 
method.  I found that the vmware driver was re-using it's get_info method 
for get_diagnostics which led to bug 1237622 [2] but overall caused some 
confusion about the difference between the compute driver's get_info and 
get_diagnostics mehods.  It looks like get_info is mainly just used to get 
the power_state of the instance.

First, the get_info method has a nice docstring for what it needs returned 
[3] but the get_diagnostics method doesn't [4].  From looking at the API 
docs [5], the diagnostics API basically gives an example of values to get 
back which is completely based on what the libvirt driver returns. Looking 
at the xenapi driver code, it looks like it does things a bit differently 
than the libvirt driver (maybe doesn't return the exact same keys, but it 
returns information based on what Xen provides).

I'm thinking about implementing the diagnostics API for the powervm driver 
but I'd like to try and get some help on defining just what should be 
returned from that call.  There are some IVM commands available to the 
powervm driver for getting hardware resource information about an LPAR so 
I think I could implement this pretty easily.

I think it basically comes down to providing information about the 
processor, memory, storage and network interfaces for the instance but if 
anyone has more background information on that API I'd like to hear it.

[1] 
https://github.com/openstack/tempest/commit/da0708587432e47f85241201968e6402190f0c5d 

[2] https://bugs.launchpad.net/nova/+bug/1237622 
[3] 
https://github.com/openstack/nova/blob/2013.2.rc1/nova/virt/driver.py#L144 

[4] 
https://github.com/openstack/nova/blob/2013.2.rc1/nova/virt/driver.py#L299 

[5] http://paste.openstack.org/show/48236/ 



Thanks,

MATT RIEDEMANN
Advisory Software Engineer
Cloud Solutions and OpenStack Development

Phone: 1-507-253-7622 | Mobile: 1-507-990-1889
E-mail: mriedem at us.ibm.com


3605 Hwy 52 N
Rochester, MN 55901-1407
United States
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20131010/0881f840/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/gif
Size: 1851 bytes
Desc: not available
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20131010/0881f840/attachment.gif>


More information about the OpenStack-dev mailing list