[ovs-dev] [PATCH 1/1] vswitchd: Allow setting MAC on DPDK interfaces

Ben Pfaff blp at ovn.org
Tue Jan 7 00:25:35 UTC 2020


On Fri, Jan 03, 2020 at 03:56:59PM +0100, Ilya Maximets wrote:
> Ben, do you see any other drawbacks that we should handle if we'll allow
> changing MAC addresses for non-internal ports?  Or, maybe some issues with
> my logic?

It can cause surprises for interactions with regular system tools.
Anyone who uses "ip" or "ifconfig" to change the MAC will find it
changed back later (perhaps not immediately).  And if you un-set it in
the database, OVS doesn't know what to change it back to.

These drawbacks aren't there in the same way for devices that OVS "owns"
like internal devices or dpdk devices.  Well, I guess they are for OVS
internal devices to some extent, but for those OVS has some
responsibility to pick a reasonable MAC address to begin with.  If OVS
doesn't, then it causes confusion of its own through things like having
a machine's MAC address change if you create a bridge and move a
physical NIC onto it.  We had lots of experience with that early on with
OVS.


More information about the dev mailing list