Red Hat Linux Enterprise (RHEL) 6.3, 6.4, and 6.5 do not support online disk re-sizing of VirtIO devices. To re-size a VirtIO device, the guest must be fully shut down and re-started.
You can use the following methods to resize the devices.
To grow devices
- Grow the storage.
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If the storage device is a VxVM Volume, re-size the volume.
# vxassist -g <diskgroup> growto <volume> <new_len>
If the storage device is a LUN from a storage array, re-size the device on the array.
- Update the size of the disk device in the host.
Stop all virtual machines using the storage device.
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If the device is a LUN from a storage array, update the size of the device:
# blockdev --rereadpt device
Restart the virtual machines.
- Update the size of the storage device in the guest .
If VxVM is managing the storage in the guest, use the vxdisk resize command.
If VxVM is not managing the storage in the guest, see the appropriate documentation.
To shrink devices
- Update the size of the disk device in the guest.
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If VxVM is managing the device in the guest, if necessary, first use the vxresize utility to shrink any file systems and volumes which are using the device. Use the vxresize utility to update the size of the public region of the device:
# vxdisk resize access_name length=new_size
If VxVM is not managing the storage in the guest, see the appropriate documentation.
- Shrink the storage in the guest.
If the device is a VxVM volume, shrink the volume with the vxassist utility.
If the device is a LUN from a storage array, shrink the device on storage array.
- Update the size of the disk device in the host.
Stop the guests which are using the devices.
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If the device is a LUN from a storage array, use the following command:
# blockdev --rereadpt device
- Start the guests.
