10.5. Dynamically Changing a Host Physical Machine or a Network Bridge that is Attached to a Virtual NIC


This section demonstrates how to move the vNIC of a guest virtual machine from one bridge to another while the guest virtual machine is running without compromising the guest virtual machine
  1. Prepare guest virtual machine with a configuration similar to the following:
    <interface type='bridge'>
          <mac address='52:54:00:4a:c9:5e'/>
          <source bridge='virbr0'/>
          <model type='virtio'/>
    </interface>
    
  2. Prepare an XML file for interface update:
    # cat br1.xml
    <interface type='bridge'>
          <mac address='52:54:00:4a:c9:5e'/>
          <source bridge='virbr1'/>
          <model type='virtio'/>
    </interface>
    
  3. Start the guest virtual machine, confirm the guest virtual machine's network functionality, and check that the guest virtual machine's vnetX is connected to the bridge you indicated.
    # brctl show
    bridge name     bridge id               STP enabled     interfaces
    virbr0          8000.5254007da9f2       yes                  virbr0-nic
    
    vnet0
    virbr1          8000.525400682996       yes                  virbr1-nic
    
  4. Update the guest virtual machine's network with the new interface parameters with the following command:
    # virsh update-device test1 br1.xml 
    
    Device updated successfully
    
    
  5. On the guest virtual machine, run service network restart. The guest virtual machine gets a new IP address for virbr1. Check the guest virtual machine's vnet0 is connected to the new bridge(virbr1)
    # brctl show
    bridge name     bridge id               STP enabled     interfaces
    virbr0          8000.5254007da9f2       yes             virbr0-nic
    virbr1          8000.525400682996       yes             virbr1-nic     vnet0
    
Red Hat logoGithubRedditYoutubeTwitter

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.

© 2024 Red Hat, Inc.