[Bug 850206] [NEW] cloud-init should try harder to get domainname in fallback case

[Scott Moser]

Public bug reported:

Right now, if there is no 'local-hostname' in a DataSource's meta-data,
then cloud-init will default the domain portion of the fqdn to be
'localdomain'.   I did this because determining a system's fully
qualified domain name is non-trivial, especially if this is occuring
while network interfaces might be coming up or are not up.  See the
manpage of 'hostname' for warnings around '--fqdn'.

This was affecting our cobbler based installed systems. The
ensemble/juju scripts were using 'hostname -f' to get a hostname that
would be reachable.  (That is still non-ideal due to the issues in
hostname(1)).

These instances would be provisioned to have an entry in /etc/hosts like:
 IP FQDN ALIAS [ALIAS2 [ ... ] ]
but cloud-init would then update the entry to have 'localdomain' as there was no local-hostname.

So, The solution proposed is:


- boot instance with old cloud-init
- verify it has cloud-init written entry in /etc/hosts
  127.0.1.1     server-912.localdomain server-912
  on ec2, 'localdomain' would be 'internal'.  In either case,  modify this, so that it the domain is 'mydomain' rather than 'localdomain' (so you can verify cloud-init changed that after reboot)
- add seed content without a local-hostname
  sudo rm -Rf /var/lib/cloud/
  sudo mkdir -p /var/lib/cloud/seed/nocloud-net
  python -c 'import boto.utils, pprint; md=boto.utils.get_instance_metadata(); del md["local-hostname"]; pprint.pprint(md);' > /tmp/meta-data
  sudo cp /tmp/meta-data /var/lib/cloud/seed/nocloud-net/meta-data
  sudo touch /var/lib/cloud/seed/nocloud-net/user-data
- sudo reboot

# after reboot, 'hostname -f' should will show 'localdomain'
# $ hostname -f
# server-912.localdomain
# and /etc/hosts has been updated by cloud-init.

That is the bug we want to fix.
With our fixed available, we can then:

- now, update /etc/hosts to have '$(hostname).mydomain' again
  sudo sed -i '/^127.0.1.1/d' /etc/hosts
  echo "127.0.1.1 $(hostname).mydomain $(hostname)" | sudo tee -a /etc/hosts

- now, install new cloud-init
  sudo dpkg -i cloud-init_0.6.2_all.deb
- clean meta-data
  for d in /var/lib/cloud/*; do [ "${d%seed}" = "$d" ] && sudo rm -Rf $d; done
- reboot
- verify that the host should now have:
  $ hostname -f
  server-912.mydomain

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: cloud-init 0.6.1-0ubuntu17
ProcVersionSignature: User Name 3.0.0-11.17-virtual 3.0.4
Uname: Linux 3.0.0-11-virtual x86_64
ApportVersion: 1.22.1-0ubuntu2
Architecture: amd64
Date: Wed Sep 14 17:13:08 2011
Ec2AMI: ami-00000085
Ec2AMIManifest: FIXME
Ec2AvailabilityZone: nova
Ec2InstanceType: m1.small
Ec2Kernel: unavailable
Ec2Ramdisk: unavailable
PackageArchitecture: all
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: cloud-init
UpgradeStatus: No upgrade log present (probably fresh install)

** Affects: cloud-init
     Importance: Undecided
     Assignee: Scott Moser (smoser)
         Status: In Progress

** Affects: cloud-init (Ubuntu)
     Importance: Medium
     Assignee: Scott Moser (smoser)
         Status: Confirmed


** Tags: amd64 apport-bug ec2-images oneiric

-- 
You received this bug notification because you are a member of Ubuntu
Server Team, which is subscribed to cloud-init in Ubuntu.
https://bugs.launchpad.net/bugs/850206

Title:
  cloud-init should try harder to get domainname in fallback case

To manage notifications about this bug go to:
https://bugs.launchpad.net/cloud-init/+bug/850206/+subscriptions