<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
  </head>
  <body style="background-color: rgb(255, 255, 255); color: rgb(0, 0,
    0); font-family: Tahoma; font-size: 16px;" text="#000000"
    bgcolor="#FFFFFF">
    <div class="QCMcontainer" style="font-family:Tahoma;font-size:16px;"><font
        face="Tahoma">Hey Jean-Philippe,<br>
        <br>
        <font face="Tahoma"><font face="Tahoma">No<font face="Tahoma">,
              after I disast<font face="Tahoma">erously
                split-brained/partitioned <font face="Tahoma">my
                  rabbitmq and <font face="Tahoma">galera <font
                      face="Tahoma"><font face="Tahoma">clusters</font>
                      by allowing <font face="Tahoma">LXC to start <font
                          face="Tahoma">the containers</font> up <font
                          face="Tahoma">without the dnsmasq process to <font
                            face="Tahoma">address their eth0 interfaces
                            (due to <font face="Tahoma">what _may_ be a
                              template/Xenial bug)</font>, I<font
                              face="Tahoma">'ve </font>spent <font
                              face="Tahoma">the last few days</font> <font
                              face="Tahoma">cleaning up<font
                                face="Tahoma"> <font face="Tahoma">the</font>
                                mess<font face="Tahoma"><font
                                    face="Tahoma"> :)</font><br>
                                  <br>
                                  <font face="Tahoma">I have two<font
                                      face="Tahoma"> unused hosts set
                                      aside as a test environment for
                                      pre-testing<font face="Tahoma">,
                                        and I'll be <font face="Tahoma">leveraging
                                          <font face="Tahoma">these in
                                            the next few days to test
                                            the<font face="Tahoma"> <font
                                                face="Tahoma">issue on <font
                                                  face="Tahoma">a fresh
                                                  Xenial install.<br>
                                                  <br>
                                                  <font face="Tahoma"><font
                                                      face="Tahoma">I'll
                                                      update you <font
                                                        face="Tahoma">(and
                                                        the list) once
                                                        I've positively
                                                        confirmed the
                                                        issue.<br>
                                                        <br>
                                                        <font
                                                          face="Tahoma">Che<font
                                                          face="Tahoma">ers!<br>
                                                          <font
                                                          face="Tahoma">D</font><br>
                                                          </font></font></font></font></font><br>
                                                </font></font></font></font></font></font></font></font></font><br>
                                <br>
                              </font></font></font></font></font></font></font></font></font></font></font></font></font><br>
      <div class="moz-cite-prefix">On 12/12/2017 21:52, Jean-Philippe
        Evrard wrote:<br>
      </div>
      <blockquote type="cite"
cite="mid:CAEhFLkSs7m7A=bNac0xA26O-D_jr92RH=tU0e_xs7eZj9ySjog@mail.gmail.com"
        style="font-size: medium;">
        <pre wrap="">Hello David,

Did you solve your issue?
Did you check that it depends on the default container interface's mtu itself?

Best regards,
JP


On 6 December 2017 at 18:45, David Young <a class="moz-txt-link-rfc2396E" href="mailto:davidy@funkypenguin.co.nz"><davidy@funkypenguin.co.nz></a> wrote:
</pre>
        <blockquote type="cite">
          <pre wrap="">So..

On 07/12/2017 03:12, Jean-Philippe Evrard wrote:

For the mtu, it would be impactful to do it on a live environment. I
expect that if you change the container configuration, it would
restart.

It’s a busy lab environment, but given that it’s fully HA (2 controllers), I
didn’t anticipate a significant problem with changing container
configuration one-at-a-time.

However, the change has had an unexpected side effect - one of the
controllers (I haven’t rebooted the other one yet) seems to have lost the
ability to bring up lxcbr0, and so while it can start all its containers,
none of them have any management connectivity on eth0, which of course
breaks all sorts of things.

I.e.

root@nbs-dh-10:~# systemctl status networking.service
● networking.service - Raise network interfaces
   Loaded: loaded (/lib/systemd/system/networking.service; enabled; vendor
preset: enabled)
  Drop-In: /run/systemd/generator/networking.service.d
           └─50-insserv.conf-$network.conf
   Active: failed (Result: exit-code) since Thu 2017-12-07 06:37:00 NZDT;
14min ago
     Docs: man:interfaces(5)
  Process: 2717 ExecStart=/sbin/ifup -a --read-environment (code=exited,
status=1/FAILURE)
  Process: 2656 ExecStartPre=/bin/sh -c [ "$CONFIGURE_INTERFACES" != "no" ]
&& [ -n "$(ifquery --read-environment --list --exclude=lo)" ] && udevadm
settle (code=e
 Main PID: 2717 (code=exited, status=1/FAILURE)

Dec 07 06:36:58 nbs-dh-10 systemd[1]: Starting Raise network interfaces...
Dec 07 06:36:58 nbs-dh-10 ifup[2717]: RTNETLINK answers: Invalid argument
Dec 07 06:36:58 nbs-dh-10 ifup[2717]: /sbin/ifup: waiting for lock on
/run/network/ifstate.enp4s0
Dec 07 06:36:58 nbs-dh-10 ifup[2717]: /sbin/ifup: waiting for lock on
/run/network/ifstate.br-mgmt
Dec 07 06:37:00 nbs-dh-10 ifup[2717]: /sbin/ifup: waiting for lock on
/run/network/ifstate.br-vlan
Dec 07 06:37:00 nbs-dh-10 ifup[2717]: Failed to bring up lxcbr0.
Dec 07 06:37:00 nbs-dh-10 systemd[1]: networking.service: Main process
exited, code=exited, status=1/FAILURE
Dec 07 06:37:00 nbs-dh-10 systemd[1]: Failed to start Raise network
interfaces.
Dec 07 06:37:00 nbs-dh-10 systemd[1]: networking.service: Unit entered
failed state.
Dec 07 06:37:00 nbs-dh-10 systemd[1]: networking.service: Failed with result
'exit-code'.
root@nbs-dh-10:~#

I’ve manually reversed the “lxc.network.mtu = 1550” entry in
/etc/lxc/lxc-openstack.conf, but this doesn’t seem to have made a
difference.

What’s also odd is that lxcbr0 appears to be perfectly normal:

root@nbs-dh-10:~# brctl show lxcbr0
bridge name    bridge id        STP enabled    interfaces
lxcbr0        8000.fe0a7fa28303    no        04063403_eth0
                            075266dc_eth0
                            160c9b30_eth0
                            38ac19ae_eth0
                            4f57300f_eth0
                            59b2b5a5_eth0
                            5b7bbeb4_eth0
                            64a1fcdd_eth0
                            6c99f5fe_eth0
                            6f93ebb2_eth0
                            70ce61e5_eth0
                            745ba80d_eth0
                            85df2fa5_eth0
                            99e6adf8_eth0
                            cbdfa2f3_eth0
                            e15dc279_eth0
                            ea67ce7e_eth0
                            ed5c7af9_eth0
root@nbs-dh-10:~#

… But, no matter the value of lxc.network.mtu, it doesn’t change from 1500
(I suppose this could actually have reduced itself based on the lower MTUs
of the member interfaces though):

root@nbs-dh-10:~# ifconfig lxcbr0
lxcbr0    Link encap:Ethernet  HWaddr fe:0c:5d:1c:36:da
          inet addr:10.0.3.1  Bcast:10.0.3.255  Mask:255.255.255.0
          inet6 addr: fe80::f4b0:bff:fec3:63b0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:499 errors:0 dropped:0 overruns:0 frame:0
          TX packets:10 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:128882 (128.8 KB)  TX bytes:828 (828.0 B)

root@nbs-dh-10:~#

Any debugging suggestions?

Thanks,
D
</pre>
        </blockquote>
      </blockquote>
      <br>
    </div>
  </body>
</html>