maas-dhcp-server should be configured to start after all network interfaces it serves are up

[James Page]

The maas-dhcp-server upstart configuration starts on the standard runlevels, but the dhcpd daemon is configured to listen on specific network interfaces only.

If this is not the first network interface, the dhcpd server can fail to start correct.

'start on net-device-up IFACE=<the right one>' would make sense - probably as an override (/etc/init/maas-dhcp-server.override)

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: maas 1.4+bzr1820+dfsg-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-5.20-generic 3.13.0
Uname: Linux 3.13.0-5-generic x86_64
ApportVersion: 2.13.1-0ubuntu2
Architecture: amd64
Date: Fri Jan 31 13:52:28 2014
InstallationDate: Installed on 2014-01-23 (8 days ago)
InstallationMedia: Ubuntu-Server 13.10 "Saucy Salamander" - Release amd64 (20131016)
PackageArchitecture: all
SourcePackage: maas
UpgradeStatus: Upgraded to trusty on 2014-01-23 (8 days ago)

[Julian Edwards (julian-edwards)]

Hi James - I am not sure this deserves a MAAS task since MAAS itself restarts the DHCP server when it alters the its config. And if it's not coming up properly at boot after it's already configured, it's a packaging bug I think?

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Dan Poler (l-dan)]

So if I'm reading James' comments correctly, this bug is not a little deal. Both Akash and I have encountered this in customer environments, and it leads to dhcpd not coming up when the interface is configured in MAAS. This is a non-obvious failure state and subsequently leads to several hours of hair-tearing-out trying to figure out why MAAS isn't booting a client system... Until you says to yourself, you says, "nah, it couldn't be something as silly as dhcpd not starting up when I configured the interface..."

It's not _necessarily_ a packaging bug as I would think that dhcpd needs to be told to Do The Right Thing (tm) whenever a network configuration is adjusted for any reason - add interface, remove interface, change IP range, etc.

[Julian Edwards (julian-edwards)]

@Dan, when the interface is configured in MAAS, it will immediately restart the DHCPD. If it does not, that is a separate problem to this one, but check that the celery.log contains no errors.

[Dan Poler (l-dan)]

@Julian,
I have not found that to be the case but will reproduce in a clean
environment to make sure
D

On Wednesday, April 23, 2014, Julian Edwards <email address hidden>
wrote:

> @Dan, when the interface is configured in MAAS, it will immediately
> restart the DHCPD. If it does not, that is a separate problem to this
> one, but check that the celery.log contains no errors.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1274944
>
> Title:
> maas-dhcp-server should be configured to start after all network
> interfaces it serves are up
>
> Status in MAAS:
> Incomplete
> Status in “maas” package in Ubuntu:
> Confirmed
>
> Bug description:
> The maas-dhcp-server upstart configuration starts on the standard
> runlevels, but the dhcpd daemon is configured to listen on specific
> network interfaces only.
>
> If this is not the first network interface, the dhcpd server can fail
> to start correct.
>
> 'start on net-device-up IFACE=<the right one>' would make sense -
> probably as an override (/etc/init/maas-dhcp-server.override)
>
> ProblemType: Bug
> DistroRelease: Ubuntu 14.04
> Package: maas 1.4+bzr1820+dfsg-0ubuntu1
> ProcVersionSignature: Ubuntu 3.13.0-5.20-generic 3.13.0
> Uname: Linux 3.13.0-5-generic x86_64
> ApportVersion: 2.13.1-0ubuntu2
> Architecture: amd64
> Date: Fri Jan 31 13:52:28 2014
> InstallationDate: Installed on 2014-01-23 (8 days ago)
> InstallationMedia: Ubuntu-Server 13.10 "Saucy Salamander" - Release
> amd64 (20131016)
> PackageArchitecture: all
> SourcePackage: maas
> UpgradeStatus: Upgraded to trusty on 2014-01-23 (8 days ago)
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/maas/+bug/1274944/+subscriptions
>

--
Dan Poler
Sent from my mobile device

[Dustin Kirkland  (kirkland)]

I've hit this a number of times too. I'm marking the priority (at least on the maas packaging task) high. Broken DHCP server renders MAAS pretty unusable.

[Andres Rodriguez (andreserl)]

James:

 > The maas-dhcp-server upstart configuration starts on the standard runlevels, but the dhcpd daemon is configured to listen on specific network interfaces only.

isc-dhcp-server is also configured to start on standard runlevels. It defaults to all interfaces in /etc/default/isc-dhcp-server. Now I'm wondering, how is this affected if I input particular interfaces in /etc/default/isc-dhcp-server and keep the upstart job to start on standard runlevels... this would mean that isc-dhcp-server is affected by the same issue, right?

If so, then we need to figure out a way to make this fix in isc-dhcp-server first, and then we will deal it in MAAS.

[Ricardo Bánffy (rbanffy)]

Does this bug affects 1.7

[Launchpad Janitor (janitor)]

[Expired for maas (Ubuntu) because there has been no activity for 60 days.]

[Launchpad Janitor (janitor)]

[Expired for MAAS because there has been no activity for 60 days.]