hostname for Xenial bare metal comes up as "ubuntu"

[Tom Luong]

I was able to build an Ubuntu Xenial image using DiB 2.2 after some hacking. Please refer to https://bugs.launchpad.net/diskimage-builder/+bug/1627402

However, something is broken with cloud-init within DiB. The hostname comes up at "ubuntu."

Dmesg shows "[ 45.279032] systemd[1]: Set hostname to <ubuntu>."

log from /var/log/cloud-init.log:
2017-03-30 21:52:54,712 - handlers.py[DEBUG]: start: init-network/config-set_hostname: running config-set_hostname with frequency once-per-instance
2017-03-30 21:52:54,712 - util.py[DEBUG]: Writing to /var/lib/cloud/instances/iid-datasource-none/sem/config_set_hostname - wb: [420] 25 bytes
2017-03-30 21:52:54,713 - helpers.py[DEBUG]: Running config-set_hostname using lock (<FileLock using file '/var/lib/cloud/instances/iid-datasource-none/sem/config_set_hostname'>)
2017-03-30 21:52:54,713 - util.py[DEBUG]: Reading from /etc/hosts (quiet=False)
2017-03-30 21:52:54,713 - util.py[DEBUG]: Read 221 bytes from /etc/hosts
2017-03-30 21:52:54,713 - util.py[DEBUG]: Reading from /etc/hosts (quiet=False)
2017-03-30 21:52:54,713 - util.py[DEBUG]: Read 221 bytes from /etc/hosts
2017-03-30 21:52:54,713 - cc_set_hostname.py[DEBUG]: Setting the hostname to ubuntu (ubuntu)
2017-03-30 21:52:54,713 - util.py[DEBUG]: Reading from /etc/hostname (quiet=False)
2017-03-30 21:52:54,713 - util.py[DEBUG]: Read 7 bytes from /etc/hostname
2017-03-30 21:52:54,713 - util.py[DEBUG]: Writing to /etc/hostname - wb: [420] 7 bytes
2017-03-30 21:52:54,714 - __init__.py[DEBUG]: Non-persistently setting the system hostname to ubuntu
2017-03-30 21:52:54,714 - util.py[DEBUG]: Running command ['hostname', 'ubuntu'] with allowed return codes [0] (shell=False, capture=True)
2017-03-30 21:52:54,716 - handlers.py[DEBUG]: finish: init-network/config-set_hostname: SUCCESS: config-set_hostname ran successfully

log from /var/log/cloud-init-output.log:
Cloud-init v. 0.7.9 running 'init-local' at Thu, 30 Mar 2017 21:50:44 +0000. Up 41.78 seconds.
Cloud-init v. 0.7.9 running 'init' at Thu, 30 Mar 2017 21:50:48 +0000. Up 45.23 seconds.
ci-info: +++++++++++++++++++++++++++Net device info++++++++++++++++++++++++++++
ci-info: +--------+-------+-----------+-----------+-------+-------------------+
ci-info: | Device | Up | Address | Mask | Scope | Hw-Address |
ci-info: +--------+-------+-----------+-----------+-------+-------------------+
ci-info: | lo | True | 127.0.0.1 | 255.0.0.0 | . | . |
ci-info: | lo | True | ::1/128 | . | host | . |
ci-info: | ens2f0 | False | . | . | . | 8c:dc:d4:0e:68:20 |
ci-info: | ens2f1 | False | . | . | . | 8c:dc:d4:0e:68:24 |
ci-info: +--------+-------+-----------+-----------+-------+-------------------+
2017-03-30 21:50:48,134 - url_helper.py[WARNING]: Calling 'http://169.254.169.254/2009-04-04/meta-data/instance-id' failed [0/120s]: request error [HTTPConnectionPool(host='169.254.169.254', port=80): Max retries exceeded with url: /2009-04-04/meta-data/instance-id (Caused by NewConnectionError('<requests.packages.urllib3.connection.HTTPConnection object at 0x7f899f65c358>: Failed to establish a new connection: [Errno 101] Network is unreachable',))]
2017-03-30 21:50:49,137 - url_helper.py[WARNING]: Calling 'http://169.254.169.254/2009-04-04/meta-data/instance-id' failed [1/120s]: request error [HTTPConnectionPool(host='169.254.169.254', port=80): Max retries exceeded with url: /2009-04-04/meta-data/instance-id (Caused by NewConnectionError('<requests.packages.urllib3.connection.HTTPConnection object at 0x7f899f65cf98>: Failed to establish a new connection: [Errno 101] Network is unreachable',))]
2017-03-30 21:50:50,139 - url_helper.py[WARNING]: Calling 'http://169.254.169.254/2009-04-04/meta-data/instance-id' failed [2/120s]: request error [HTTPConnectionPool(host='169.254.169.254', port=80): Max retries exceeded with url: /2009-04-04/meta-data/instance-id (Caused by NewConnectionError('<requests.packages.urllib3.connection.HTTPConnection object at 0x7f899f669588>: Failed to establish a new connection: [Errno 101] Network is unreachable',))]

[Diogenes (splash-gmail)]

I think this problem is because of this line:
https://github.com/openstack/diskimage-builder/blob/master/diskimage_builder/elements/debootstrap/install.d/10-debian-networking#L25