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Attached volume to instance is not listed as disk in OS installing

asked 2018-10-31 04:04:13 -0500

soheil08 gravatar image

updated 2018-10-31 06:48:38 -0500


I've installed PackStack on two nodes, one node is running as controller and network and the other node is compute node. I Created a project and add an image of CentOS. After that, I created an instance using that image along with a volume of size 20 GB, named TestInstance. When I run TestInstance to install CentOS, in selecting disk setting, there are no items! This while in OpenStack dashboard I can see the volume is created and attached to the instance (I've done all these using dashboard). There is a file in the path /dev/cinder-volumes with the id of attached volume, too. I checked the cinder logs and there was no error, but I found out the host of the created volume is None!

This line in logs show OpenStack doesn't know about the host:

2018-10-31 12:06:27.502 2589 INFO cinder.volume.manager [req-7473204b-4ae9-46c6-8311-8c75d011e42b e02403adc21242b48f105162106edbc4 d7a6d4ba7e3b47c3bf5060577aceb5a7 - default default] Attaching volume 234350a4-e847-4ff9-a379-70a09aaee187 to instance 6fa515c4-2905-4023-b88b-71d9c3af57d1 at mountpoint /dev/vda on host None.

On the other hand, using the command line there is no record in the output of the "cinder list" command. But when I create a volume using the command "cinder create 10 --display-name my-new-volume --availability-zone nova", it successfully created and I can see it in the output of "cinder list" command.

I guess somewhere in cinder config I should set compute node address to use it as host. Any suggestion would be appreciated.

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answered 2018-11-01 01:23:48 -0500

tze gravatar image

First of all, when you create an instance the system copies the image (Centos in your case) to local ephemeral disk called root disk. This disk will deleted when the instance delete. You can change this with create a Volume from image and the boot instance from volume. In this case the volume will be available when the instance will be died. Now in the instance, the root disk or volume is connected as an emulated device. The os that you try to install must has drivers for this type of emulated disk. You must check in Nova project what properties you must apply to your image to tell the Nova what kind of disk will create (scsi, idea etc). It's something like scsi controllers that you need extra drivers if you try to install old os on them.

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Asked: 2018-10-31 04:04:13 -0500

Seen: 733 times

Last updated: Nov 01 '18