Virsh interface move

vifmove.sh

#!/bin/bash
# usage ~/vifmove.sh <virsh_domain_name/id> <interface_name> <new_bridge_name>
tmpxml=$(mktemp /tmp/ifcfg.XXX)
macaddr="$(virsh domiflist $1 | awk "/$2\s/ {print \$NF}")"
cat > "$tmpxml" <<EOF
<interface type='bridge'>
    <mac address='$macaddr'/>
    <source bridge='$3'/>
    <model type='virtio'/>
</interface>
EOF
virsh update-device "$1" "$tmpxml" --live --persistent
rm "$tmpxml"

Blog post -- https://netdevops.me/2017/changing-libvirt-bridge-attachment-in-a-running-domain-aka-on-the-fly/

#!/bin/bash
# usage ~/vifmove.sh <virsh_domain_name/id> <interface_name> <new_bridge_name>
function update_bridge() {
  tmpxml=$(mktemp /tmp/ifcfg.XXX)
  macaddr="$(virsh domiflist $1 | awk "/$2\s/ {print \$NF}")"
  model="$(virsh domiflist $1 | awk "/$2\s/ {print \$4F}")"

  cat > "$tmpxml" <<EOF
<interface type='bridge'>
<mac address='$macaddr'/>
<source bridge='$3'/>
<model type='$model'/>
</interface>
EOF
  virsh update-device "$1" "$tmpxml" --live
  rm "$tmpxml"
}

for domain in $(virsh list --uuid); do
  update_bridge $domain $1 $2
done

I've added some bits to do all VMs in a batch.

Added this to the end, for interfaces that have DHCP, it will bring it down and back up to refresh network. Note this only works for one interface, assumes you have DHCP in the guest, but the original script only assumes one interface per bridge anyway.

#!/bin/bash
# usage ~/vifmove.sh <virsh_domain_name/id> <interface_name> <new_bridge_name>
tmpxml=$(mktemp /tmp/ifcfg.XXX)
macaddr="$(virsh domiflist $1 | awk "/$2\s/ {print \$NF}")"
cat > "$tmpxml" <<EOF
<interface type='bridge'>
<mac address='$macaddr'/>
<source bridge='$3'/>
<model type='virtio'/>
</interface>
EOF
virsh update-device "$1" "$tmpxml" --live --persistent
rm "$tmpxml"
netintface=`virsh domiflist $1 | grep $3 | awk '{print $1}'`
echo $netintface
virsh domif-setlink "$1" $netintface down
sleep 2
virsh domif-setlink "$1" $netintface up