How do I map a virtual machine’s disks and network interfaces on a dedicated host?
A guest’s virtual disk and virtual NIC are connected to host-side resources that must be understood before maintenance. A disk may be a file, logical volume or network storage object; a NIC may use a bridge, managed network or direct attachment. Inspect the selected guest and connection rather than inferring these relationships from names alone.
Before you start
- Authorised access to the intended libvirt system connection.
Instructions
1. Identify the correct libvirt guest
Use the system connection intended for this host. Substitute the exact guest name from the list for example-vm in the next commands.
virsh --connect qemu:///system list --allConfirm the guest’s identity and running state. A separate per-user connection may show a different inventory.
2. Read disk and interface attachments
The active configuration can differ from the configuration used after a restart. Check both views if a pending change is involved.
virsh --connect qemu:///system domblklist example-vm --details
virsh --connect qemu:///system domiflist example-vmRecord disk target/source mappings and NIC type, source and MAC address. Trace those sources to the actual storage service or bridge and its physical uplink.
Check the result
- Each guest disk and NIC has a verified host-side dependency, and a maintenance plan includes every guest affected by the selected storage or network component.
Troubleshooting
- A path is not an ordinary file
- It may identify a block volume or network storage source; use the relevant storage backend’s reporting tools.
- The guest has a NIC but no connectivity
- Inspect the host bridge/uplink, VLAN and provider MAC/IP restrictions as well as guest addressing.
- Saved and running settings differ
- Review the active versus inactive definitions before assuming a reboot preserves current behaviour.
Official references
Use the documentation for your installed version when a flag, service name or platform feature differs.