I have a fixed IP address assigned via DHCP to a machine that I just
updated to F31.
After the update, I was slightly surprised when it didn't come up on its
fixed IP address. After looking through the logs, the DHCP server is now
apparently getting a DHCP request from a different MAC address, apparently
the bridge's MAC address. I updated the DHCP config, and brought the network
connection down/up, and it came up on its fixed IP address, normally.
In F30, the kernel was kernel-5.3.11-200.fc30.x86_64, and it's now
kernel-5.3.11-300.fc31.x86_64, of course; so this doesn't look like a kernel
change.
The relevant data is:
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel master
vnet0 state UP group default qlen 1000
link/ether 00:30:48:fc:83:fa brd ff:ff:ff:ff:ff:ff
inet6 fe80::230:48ff:fefc:83fa/64 scope link
valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default
qlen 1000
link/ether 00:30:48:fc:83:fb brd ff:ff:ff:ff:ff:ff
4: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP
group default qlen 1000
link/ether 96:03:13:50:00:eb brd ff:ff:ff:ff:ff:ff
inet 192.168.0.2/24 brd 192.168.0.255 scope global dynamic vnet0
valid_lft 603710sec preferred_lft 603710sec
inet6 fe80::9403:13ff:fe50:eb/64 scope link
valid_lft forever preferred_lft forever
Up until F30, the DHCP server was seeing requests from 00:30:48:fc:83:fa,
and now the DHCP server is seeing requests from 96:03:13:50:00:eb.
I'm hoping that, at least, the bridge won't be getting random MAC addresses
with every boot?