Unique KVM setup. Hostname of KVM not making through the network bridge to DHCP server.

[Robb <robb barrows gmail com>]

I have a bit of an interesting setup, a KVM host using
CentOS 7 3.10.0-229.el7.x86_64 and
NetworkManager.x86_64 1:1.0.0-14.git20150121.b4ea599c.el7

I set up a network bridge on the host for all the KVM's to use and for 
the most part it works great, when NetworkManager is started on a KVM 
they get their IP from the DHCP server and report their hostname 
perfectly.  This allows me to access the KVM's anywhere on my network 
using just their hostname.

The issue is if my router reboots.  The KVM's interface don't seem to 
notice anything went down since they are behind the bridge, thus they 
keep their previous IP address and the rebooted router has no idea of 
their existence.

After this hostname lookup obviously doesn't work and I can only access 
them via their last known IP address.

This problem is easily solved by restarted NetworkManager on each 
individual KVM, and I could write a cron script to detect and do this, 
but I thought someone here may have a better idea.

Does anyone have any ideas on how I can get this working?  I am also 
open to other topologies that create the same effect in the end.


Here is my host setup:

# nmcli c add type bridge autoconnect yes con-name br0 ifname br0
# nmcli c modify br0 ipv4.addresses 192.168.1.100/24 ipv4.method manual
# nmcli c modify br0 ipv4.gateway 192.168.1.1
# nmcli c modify br0 ipv4.dns 192.168.1.1
# nmcli c delete enp4s0f0
# nmcli c add type bridge-slave autoconnect yes con-name enp4s0f0 ifname 
enp4s0f0 master br0
# systemctl restart NetworkManager

The KVM's do not have any special setup, they auto detect their 
connection via NetworkManager.

Any help is greatly appreciated.

-Robb