[Kimchi-devel] [PATCH] issue #312: Rename LVM while deleting logical storage pool

[Shu Ming]

于 2014/3/6 1:53, Aline Manera 写道:
> On 03/05/2014 04:50 AM, Shu Ming wrote:
>> 2014/3/5 4:49, Aline Manera:
>>> From: Aline Manera <alinefm at br.ibm.com>
>>>
>>> When creating a Logical storage pool, a LVM is created with the same
>>> name.
>>
>> I assume you mean a volume group here.
>
> Yes. I will update it
>
>>
>>> And when deleting the storage pool the LVM keeps on the system.
>>> Which is
>>> the correct behavior as the storage pool is only a concept and
>>> deleting it
>>> should not affect the file system.
>> I am a bit confusing here. The volume group was created when the user
>> tried to create a storage pool from a raw device like "/dev/sda3".
>> When the storage pool was undefined, it was reasonable to remove the
>> volume group and make the raw device available again. Is it?
>>
>
> No. As I said deleting a storage pool does not affect the file system
> so the vg will keep there
I would argue that.
But creating a storage pool do affect the volume group system. So it is
reasonable to undo the effect caused by creating a storage pool when
deleting the storage pool. Also, only raw empty block devices can be
used to create the storage pool in Kimchi, so it is safe to assume that
the storage pool created by Kimchi can be deleted with the volume group
under it released.

>
>>> But it prevents the user to create a new logical pool with a name used
>>> before which is odd.
>>> So when deleting a logical pool, rename the LVM to a single name to
>>> allow user create a logical pool with any name.
>> So the raw device will be used after the renaming and will not be
>> available any more?
>
> Once a raw device is used for a logical pool it will not a raw device
> anymore - otherwise, the user manually do it on system
> But not through kimchi.
>
>>
>>>
>>> Also convert an error message parameter to string instead of
>>> virStoragePool
>>> instance.
>>>
>>> Signed-off-by: Aline Manera <alinefm at br.ibm.com>
>>> ---
>>> src/kimchi/model/storagepools.py | 15 ++++++++++++++-
>>> 1 file changed, 14 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/src/kimchi/model/storagepools.py
>>> b/src/kimchi/model/storagepools.py
>>> index 76ab2d6..dd3c9a2 100644
>>> --- a/src/kimchi/model/storagepools.py
>>> +++ b/src/kimchi/model/storagepools.py
>>> @@ -17,6 +17,8 @@
>>> # License along with this library; if not, write to the Free Software
>>> # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
>>> 02110-1301 USA
>>>
>>> +import time
>>> +
>>> import libvirt
>>>
>>> from kimchi import xmlutils
>>> @@ -172,7 +174,8 @@ class StoragePoolModel(object):
>>> return 0
>>> except libvirt.libvirtError as e:
>>> raise OperationFailed("KCHPOOL0008E",
>>> - {'name': pool, 'err': e.get_error_message()})
>>> + {'name': pool.name(),
>>> + 'err': e.get_error_message()})
>>>
>>> def _get_storage_source(self, pool_type, pool_xml):
>>> source = {}
>>> @@ -348,7 +351,17 @@ class StoragePoolModel(object):
>>> if pool.isActive():
>>> raise InvalidOperation("KCHPOOL0005E", {'name': name})
>>> try:
>>> + xml = pool.XMLDesc(0)
>>> + pool_type = xmlutils.xpath_get_text(xml, "/pool/@type")[0]
>>> pool.undefine()
>>> + # The user may want to create a logical pool with the same name
>>> + # used before but a LVM will already exist with this name
>>> + # So rename the former LVM to avoid future conflicts
>>> + if pool_type == 'logical':
>>> + lvm_name = "%s-%s" % (name, str(int(time.time()*1000)))
>>> + vgrename_cmd = ["vgrename", name, lvm_name]
>>> + run_command(vgrename_cmd)
>>> +
>>> except libvirt.libvirtError as e:
>>> raise OperationFailed("KCHPOOL0011E",
>>> {'name': name, 'err': e.get_error_message()})
>>
>