[1.10] Unable to detect IPMI control settings during enlistment

Am trying 1.10 on Xenial and after PXE booting my machines I see them enlisted with no BMC (IPMI) settings.

Watching the console logs during enlistment I see this, which may be material:

Setting up freeipmi packages fails:

Setting up ipmitool (1.8.13-1ubuntu0.6) ...
 * Starting IPMI event daemon
Could not open device at /dev/ipmi0 or /dev/ipmi/0 or /dev/ipmidev/0: No such file or directory
   ...fail!
invoke-rc.d: initscript ipmievd, action "start" failed.
Unable to start ipmievd during installation. Trying to disable.

I then see this from cloud-init:

Cloud-init v. 0.7.5 running 'modules:final' at Tue, 02 Feb 2016 06:28:14 +0000. Up 67.20 seconds.
[ 68.566468] ipmi-locate:2572 map pfn expected mapping type uncached-minus for [mem 0xbf770000-0xbf770fff], got write-back
[ 68.577467] ipmi-locate:2572 map pfn expected mapping type uncached-minus for [mem 0xbf770000-0xbf770fff], got write-back
[... many duplicates of these lines ...]
Traceback (most recent call last):
  File "/tmp/sh.vMSQGs/bin/maas-ipmi-autodetect", line 303, in <module>
    main()
  File "/tmp/sh.vMSQGs/bin/maas-ipmi-autodetect", line 261, in main
    if not is_ipmi_dhcp() and args.dhcp:
  File "/tmp/sh.vMSQGs/bin/maas-ipmi-autodetect", line 137, in is_ipmi_dhcp
    return show_re.search(output) is not None
TypeError: can't use a string pattern on a bytes-like object
grep: write error: Broken pipe
  % Total % Received % Xferd Average Speed Time Time Time Current
                                 Dload Upload Total Spent Left Speed
100 1807 0 1586 100 221 1708 238 --:--:-- --:--:-- --:--:-- 1709

=== Tue, 02 Feb 2016 06:28:17 +0000: successfully enlisted to 'http://192.168.9.2/MAAS/api/1.0/nodes/' with hostname '192-168-9-66.cluster.maas'