Step 1: Stop the libvirtd Service

# systemctl stop libvirtd.service

You should see something like this

● libvirtd.service - Virtualization daemon
Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled; vendor preset: enabled)
Active: inactive (dead) since Mon 2019-06-03 13:33:26 +08; 43s ago
Docs: man:libvirtd(8)
https://libvirt.org
Process: 28069 ExecStart=/usr/sbin/libvirtd $LIBVIRTD_ARGS (code=exited, status=0/SUCCESS)
Main PID: 28069 (code=exited, status=0/SUCCESS)
Tasks: 2 (limit: 32768)
Memory: 6.7M
CGroup: /system.slice/libvirtd.service
├─28896 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper
└─28897 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefile-ro --dhcp-script=/usr/libexec/libvirt_leaseshelper

Step 2. Disable the service

# systemctl disable libvirtd.service

Step 3: Removing the virbr0 interfaces on machine

# brctl show

bridge name     bridge id               STP enabled     interfaces
docker0         8000.0242f3432864       no
virbr0          8000.525400d6fcaa       yes             virbr0-nic

Step 4: Down the Bridge Link

# ip link set virbr0 down

Step 5: Remove the Bridge

# brctl delbr virbr0

Step 6: Verify that the bridge has been removed.

# brtcl show

bridge name bridge id STP enabled interfaces
docker0 8000.0242f3432864 no