Making SCSI tape drive controller accessible to VM OS using virt-manager

Mike Parker

12/15/23, 11:11 AM

I'm trying to make a SCSI tape drive drive controller card (or strictly, the tape drives and robotic tape library hanging off it) visible to the OS running on the VM.

I'm running RHEL 7.9 on both the hypervisor and VM guest.

On the hypervisor, a lsscsi gives:

> lsscsi
[0:2:0:0]    disk    LSI      MR9260-4i        2.13  /dev/sda 
[5:0:0:0]    tape    IBM      ULTRIUM-HH7      G9Q1  /dev/st0 
[5:0:0:1]    mediumx BDT      FlexStor II      6.20  /dev/sch0
[5:0:1:0]    tape    IBM      ULTRIUM-HH8      P381  /dev/st1 
[12:0:8:0]   enclosu LSI      SAS2X36          0e12  -        
[12:0:9:0]   enclosu LSI      SAS2X28          0e12  -        
[12:2:0:0]   disk    LSI      MR9381-4i4e      4.27  /dev/sdb

All attempts within virt-manager to make the hypervisor /dev/{st0,st1,sch0} devices available to the VM OS as a Controller (Type SCSI), Serial device (Physical host character device), Channel device (Physical host character device) have so far failed to yield a /dev/s{t,g} device I can access with mt/mtx.

Attempting to map the SCSI controller card through to the VM OS as a PCI device also fails with a "unsupported configuration: host doesn't support passthrough of host PCI devices" error.

Where am I going wrong? How should I be mapping a /dev device on the hypervisor through to the VM OS?

1 + 0

linux

scsi

hypervisor

tapedrive

virt-manager

Score:0

Server

Juan Herrera

12/15/23, 11:46 AM

if you cannot passtrought your controller to VM you cant do anything. Please review this link about virtio iscsi https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/virtualization_administration_guide/sect-managing_storage_controllers_in_a_guest

+ 1

Mike Parker

12/15/23, 12:32 PM

Thanks, your URL put me onto the following, regarding assignment of PCI devices from the host to the VM: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/virtualization_administration_guide/chap-guest_virtual_machine_device_configuration#sect-Guest_virtual_machine_device_configuration-PCI_devices As we don't currently have the intel_iommu boot param set, we're going to give that a try

Elon Musk

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EN: Making SCSI tape drive controller accessible to VM OS using virt-manager

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