Docker install breaks virtual network bridge

Hello and good day. I am very new to using Docker. Wanting to experiment setting up a MariaDB, Apache2, Guacamole, and Owncloud servers all linked via dockers. I currently have a similar setup as Virtual machines via Qemu/KVM using Virtual Manager on an Ubuntu 19.10 desktop.
So, basically I have my virtual machines grabbing local network IP’s from my router via a virtual network bridge. Using this setup does break the managed network functionality of Ubuntu desktop, but does not break networking itself. This is accomplished by adding the following lines to my /etc/network/interfaces file: apologize if the code looks bad as I am not sure how to place code snips in this forum.

interfaces(5) file used by ifup(8) and ifdown(8)

auto lo
iface lo inet loopback

auto enp6s0
iface enp6s0 inet manual

auto virbr2
iface virbr2 inet dhcp
bridge_ports enp6s0
bridge_stp off

Before installing Docker, this worked fine. My desktop grabs the IP assigned by the router via mac address. Then the VM network cards are pointed to the virtual bridge virbr2. When they start they are getting there own IP addresses directly from my router. As soon as I install docker the docker0 virtual network bridge moves to the very top of my network adapter list and the VM’s are no longer able to grab IP addresses from the router DHCP server. The main Desktop although can still grab its IP address under the virbr2 adapter. Once I uninstalled Docker this functionally returned and all was normal again. Thoughts?

Any help would be greatly appreciated as I am still in a learning curve.
Thanks,
Mike

I am not sure if this is your problem or if the solution recommended here will solve your problem, but this is the main reason for me to not use docker on my main computer since it has a few QEMU VMs. I hope it helps!

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Though, be aware that one of the aspects of dockers usuability is that it modifies iptables rules as required to make incomming/outgoing network communication to the containers work. If you disable the iptables feature of the engine, you will have to figure out and apply the required iptables rules by yourself.