[systemd-devel] [networkd] Unable to set MTU with .link file

[Ian Pilcher]

I am tearing my hair out trying to figure out why I an unable to set the
MTU of an OVS port with a .link file.

I am trying to create this:

     +----------------+                      +----------------+
     |                |                      |                |
     |      eno1      |                      |      eno2      |
     |  (MTU = 8996)  |                      |  (MTU = 8996)  |
     |                |                      |                |
     +-------+--------+                      +-------+--------+
             |                                       |
             +-------------------+-------------------+
                                 |
                         +-------+--------+
                         |                |
                         |      bond0     |
                         |  (MTU = 8996)  |
                         |                |
                         +-------+--------+
                                 |
                         +-------+--------+
                         |                |
                         |      ovs0      |
                         |  (MTU = 8996)  |
                         |                |
                         +-------+--------+
                                 |
             +-------------------+-------------------+
             |                                       |
     +-------+--------+                      +-------+--------+
     |                |                      |                |
     |     vlan248    |                      |     vlan250    |
     |  (MTU = 8996)  |                      |  (MTU = 1500)  |
     |                |                      |                |
     +----------------+                      +----------------+

Everything works, except that vlan250 is inheriting the jumbo MTU from
ovs0.  I've created a link file to set the MTU to 1500:

/etc/systemd/network/98-vlan250.link:

     [Match]
     OriginalName=vlan250

     [Link]
     MTUBytes=1500

For some reason, this isn't working.

I've set udev_log="debug" in /etc/udev/udev.conf and rebuilt my
initramfs.  I've also created a drop-in for systemd-networkd that sets
SYSTEMD_LOG_LEVEL=debug.

A full boot log with these settings can be found at:

   http://www.penurio.us/journal.txt

Any ideas or debugging techniques very much appreciated.

-- 
========================================================================
Ian Pilcher                                         arequipeno at gmail.com
-------- "I grew up before Mark Zuckerberg invented friendship" --------
========================================================================