Hi All,
I want to upload an iso image and create instance and install from this. I want to attach volume to /dev/sda and not /dev/vda to the instance. Please note that the iso has custom OS and it expects to find the had drive to be present in /dev/sda
Any suggestions....
TIA
I just tried the following with Ocata (and Ceph as backend):
I added image properties hw_scsi_model=virtio-scsi and hw_disk_bus=scsi to an ISO image. Launching that ISO without attached disks results in /dev/sda device name in the partitioner. Then I attach new (empty) volumes to that instance, both are recognized as sdb and sdc.
EDIT: Here's the command I'm using to create an instance from ISO attached with two volumes. Please note: this worked for me only with the already mentioned image properties for the ISO. Without them, the build fails because libvirt tries to allocate one volume as vda, the other as sda. This could be the result from the bug I created almost three years ago, which is still open.
nova boot --block-device source=image,id=<ISO_IMAGE>,dest=volume,size=5,shutdown=preserve,device=sda,bootindex=0 --block-device source=blank,dest=volume,size=5,shutdown=preserve,device=sdb,bootindex=1 --nic net-id=<NET_ID> --flavor 2 test1
This results in a running instance, trying to install from ISO, two volumes are attached: 
OK, this is contrary to what i thought. Now that I think about it, of course image properties determine VM properties, so that this VM should indeed use SCSI instead of virtio.
I tried setting image properties as shown. My volume wont connect to the instance. It tries to connect using /dev/sda and fails with error.
When you boot an instance, you have a lot of flexibility how to attach a volume, including the driver. For example this should work (I didn't check):
nova boot ... --block-device id=IMAGE_ID,source=image,dest=local,bus=scsi,bootindex=0
Perhaps the openstack client has similar options.
I created an image of iso format with said properties: properties | hw_disk_bus='scsi', hw_scsi_model='virtio-scsi'
I then created an instance out of it to start the boot from iso. I then attached a empty volume already created.
It got attached to /dev/vda... Am i doing something wrong?
The image properties don’t impact volume attachments. nova volume-attach and openstack server add volume don’t seem to provide that much control, but the API does.
Or you attach the volume at boot time, using nova boot --block-device .... You can repeat the block-device option.
Asked: 2019-02-06 08:10:38 -0500
Seen: 934 times
Last updated: Feb 08 '19
