How to use virsh attach-device without knowledge of target dev name

gregthegeek

11/1/22, 4:50 AM

Is there a way to use virsh attach-device without using a target?

For example, I attach a disk by using an xml file which includes the target "sdc".

<disk type='block' device='disk'>
    <source dev='/dev/disk/by-label/mydisk' />
    <target dev='sdc' bus='scsi' />
</disk>

To speed the process I'd like to not specify a target device, only the bus. The reason for this is so I don't have to login to the guest, get the current devices used, then edit the host xml file to use a new "sdX" name, and finally then attach the disk. It would save a lot of steps to just let it attach to the next available disk device in the guest.

I'm moving enough disks in and out of the guest it's become annoying. Also, when I detach the disk, it leaves the sdX device used, so I have to edit the file and move up the letters until it works. I'd like to also be able to script this and that would be much easier if I didn't need to know what the next device available is in the guest.

If there's a way to get the next available in the guest using virsh or other kvm/qemu commands, that would be nice too.

I only use CLI - no virt manager.

EDIT: I just found "virsh domblklist", which lists the block devices on the guest, so I may look into changing to use virsh attach-disk. Just have to learn the arguments for that.

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Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: How to use virsh attach-device without knowledge of target dev name

TH: วิธีการใช้อุปกรณ์แนบ virsh โดยไม่ทราบชื่อผู้พัฒนาเป้าหมาย

RO: Cum să utilizați dispozitivul de atașare virsh fără cunoașterea numelui dezvoltatorului țintă

RU: Как использовать virsh attach-device без знания имени целевого устройства

VI: Cách sử dụng thiết bị đính kèm virsh mà không cần biết tên nhà phát triển mục tiêu

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