Bug 613546

Can you provide ~/.virt-manager/virt-manager.log or reproduce running with the --debug flag?

Certain disk types can't hotplug AIUI (like IDE, Floppy device, ...). At least virtio and USB should work. virt-manager doesn't really care though, it will always attempt a hotplug and only show that 'attach after reboot' dialog if the hotplug failed. The log should show us the relevant hotplug failure errors.

We should probably show a little 'details' expander if the hotplug fails so the user can see an error message though.

The ~/.virt-manager/virt-manager.log is as follow on usb adding:

[Tue, 13 Jul 2010 09:44:46 virt-manager 4733] DEBUG (addhardware:1060) Starting background file allocate process
[Tue, 13 Jul 2010 09:44:46 virt-manager 4733] DEBUG (addhardware:1062) Allocation completed
[Tue, 13 Jul 2010 09:44:46 virt-manager 4733] DEBUG (addhardware:1022) Adding device:
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw'/>
      <source file='/var/lib/libvirt/images/rhel55-i386.img'/>
      <target dev='sda' bus='usb'/>
    </disk>
[Tue, 13 Jul 2010 09:44:46 virt-manager 4733] DEBUG (addhardware:1029) Device could not be hotplugged: internal error unable to execute QEMU command 'drive_add': The command drive_add has not been found

It is similar with virto disk adding.

I find the similar bug 573946 about virtio hotplug on libvirt, I think the usb hotplug also has the same problem. As Cole said that there should be an error show to us when hotplug failed, but it doesn't have now.

Okay, not a critical RFE then. Moving to 6.1

Does the 'dev' in summary involve the cpu ? I found the same issue on cpu hotplug with a libvirt Bug 573597.

It can. Changing the desc.

what about the scsi hotplug? Should it be supported?

SCSI isn't supported for RHEL6 AFAIU.

Fixed upstream:

http://hg.fedorahosted.org/hg/virt-manager/rev/60f80fc312d3

Fixed in virt-manager-0.8.6-1.el6

Verified with passed in virt-manager-0.8.6-1.el6

# uname -a
Linux dhcp-65-85.nay.redhat.com 2.6.32-99.el6.x86_64 #1 SMP Fri Jan 14 10:46:00
EST 2011 x86_64 x86_64 x86_64 GNU/Linux

kernel-2.6.32-99.el6.x86_64
qemu-kvm-0.12.1.2-2.129.el6.x86_64
libvirt-0.8.7-1.el6.x86_64

===========================
Now virtio disk can support hotplug/unplug in virt-manager.Others like IDE,IDE-CDROM, Floppy will display error message when hotplug/unplug as following:

** Error message for hotplug with disk type as IDE-CDROM **

This device could not be attached to the running machine. Would you like to make the device available after the next VM shutdown?
Details:
internal error No device with bus 'ide' and target 'hdc'

Traceback (most recent call last):
  File "/usr/share/virt-manager/virtManager/addhardware.py", line 911, in add_device
    self.vm.attach_device(self._dev)
  File "/usr/share/virt-manager/virtManager/domain.py", line 1159, in attach_device
    self._backend.attachDevice(devxml)
  File "/usr/lib64/python2.6/site-packages/libvirt.py", line 263, in attachDevice
    if ret == -1: raise libvirtError ('virDomainAttachDevice() failed', dom=self)
libvirtError: internal error No device with bus 'ide' and target 'hdc'


** Error message for hotunplug disk type as IDE-CDROM **

Device could not be removed from the running machine
This change will take effect after the next VM reboot.
Details:
unsupported configuration: This type of device cannot be hot unplugged

Traceback (most recent call last):
  File "/usr/share/virt-manager/virtManager/details.py", line 1776, in remove_device
    self.vm.detach_device(dev_id_info)
  File "/usr/share/virt-manager/virtManager/domain.py", line 1169, in detach_device
    self._backend.detachDevice(xml)
  File "/usr/lib64/python2.6/site-packages/libvirt.py", line 353, in detachDevice
    if ret == -1: raise libvirtError ('virDomainDetachDevice() failed', dom=self)
libvirtError: unsupported configuration: This type of device cannot be hot unplugged

Verified this bug passed with virt-manager-0.8.6-3.el6

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2011-0637.html