5.3. Starting virtual machines automatically when the host starts

Procedure

1. Use the virsh autostart utility to configure the VM to start automatically when the host starts.

   For example, the following command configures the demo-guest1 VM to start automatically.

   # virsh autostart demo-guest1
   Domain 'demo-guest1' marked as autostarted

2. If you use network interfaces that are not managed by libvirt, you must also make additional changes to the systemd configuration. Otherwise, the affected VMs might fail to start.

   注意

   These interfaces include for example:

   • Bridge devices created by NetworkManager
   • Networks configured to use <forward mode='bridge'/>

   1. In the systemd configuration directory tree, create a virtqemud.service.d directory if it does not exist yet.

      # mkdir -p /etc/systemd/system/virtqemud.service.d/

   2. Create a 10-network-online.conf systemd unit override file in the previously created directory. The content of this file overrides the default systemd configuration for the virtqemud service.

      # touch /etc/systemd/system/virtqemud.service.d/10-network-online.conf

   3. Add the following lines to the 10-network-online.conf file. This configuration change ensures systemd starts the virtqemud service only after the network on the host is ready.

      [Unit]
      After=network-online.target

Verification

1. View the VM configuration, and check that the autostart option is enabled.

   For example, the following command displays basic information about the demo-guest1 VM, including the autostart option.

   # virsh dominfo demo-guest1
   Id:             2
   Name:           demo-guest1
   UUID:           e46bc81c-74e2-406e-bd7a-67042bae80d1
   OS Type:        hvm
   State:          running
   CPU(s):         2
   CPU time:       385.9s
   Max memory:     4194304 KiB
   Used memory:    4194304 KiB
   Persistent:     yes
   Autostart:      enable
   Managed save:   no
   Security model: selinux
   Security DOI:   0
   Security label: system_u:system_r:svirt_t:s0:c873,c919 (enforcing)

2. If you use network interfaces that are not managed by libvirt, check if the content of the 10-network-online.conf file matches the following output.

   $ cat /etc/systemd/system/virtqemud.service.d/10-network-online.conf
   [Unit]
   After=network-online.target