Return server error when we make 'Confirm or Revert Resize instance'

[Alexey Galkin]

Find on mos 8.0 iso #478

Stepts to reproduce:

1. Login to horizon.
2. Create a new instance.
3. Navigate to Project->Compute->Instances and click dropdown menu in Instance`s row.
4. Click on Resize Instance menu item
5. From opened form select other flavor ('m1.micro', for example) > select Resize button.
6. Instance is resizing (status 'Resize/Migrate') and then return to status "Confirm or Revert Resize/Migrate".
7. Select Confirm Resize/Migrate button in Instance`s row, after this button should be disable (3-5 sec), and then becomes active again until instance will not be resized and return to status Active.

And if we press button while instance will not be return to status Active, then horizon return a 'server error' message:

""""
Something went wrong!

An unexpected error has occurred. Try refreshing the page. If that doesn't help, contact your local administrator.
""""

[Timur Sufiev (tsufiev-x)]

Setting as Won't Fix for 8.0 due to our policies.

Just checked it on a fresh Mitaka release Devstack - haven't encountered this error.

Sergei, could you please try to reproduce it for MOS 9.0 release?

[Sergei Chipiga (schipiga)]

Not confirmed for MOS8.0.

When I try to resize down, after page reload nothing happens, the instance has the same size. But inside log there is ResizeError: Resize error: Unable to resize disk down.

@tsufiev-x, I suppose, it's a good point to show allert message "Unable to resize disk down", because current behavior is unclear.

[Sergei Chipiga (schipiga)]

@tsufiev-x, confirmed for MOS9.0

[Timur Sufiev (tsufiev-x)]

Sergei, thanks, that makes the situation clearer.

[Vitaly Sedelnik (vsedelnik)]

Won't Fix for 8.0-updates because of Medium importance

[Sergei Chipiga (schipiga)]

checked with mos9.0#138, fixed

[Sergei Chipiga (schipiga)]

Checked with mos9.0#188

Still can't resize from small to tiny. And no messages that not possible to resize down.

[Sergei Chipiga (schipiga)]

Problem with resize "small" -> "tiny" is present only without ceph.
If to use Ceph:
- Ceph RBD for volumes (Cinder)
- Ceph RadosGW for objects (Swift API)
- Ceph RBD for ephemeral volumes (Nova)
- Ceph RBD for images (Glance)
resize "small" -> "tiny" works fine.

Steps to reproduce:
- Deploy openstack without cepth
- Login as admin
- Launch instance with flavor tiny
- Resize it to flavor small
- Resize it to flavor tiny

Expected result:
- Instance will be resized to tiny, or there will be alert, that can't resize down (dependent of backend logic)

Actual result:
- Nothing happens, instance has still small flavor. There is notification that resize is scheduled only.

[Dina Belova (dbelova)]

Added move-to-10.0 tag due to the fact bug was transferred from 9.0 to 10.0