Comment 4 for bug 1069570

Revision history for this message
Raphaƫl Badin (rvb) wrote : Re: 1 MAC Address, two IPs - DNS is "out of sync" with DHCP leases databases, I think...

Actually, I think you're seeing two distinct problems here:

- The first one is that the default hostname picked up during enlistment is IP-based and thus it assumes that the IP lease will stay the same. If the lease changes, this change is not reflected in the DNS config because this is resolved by a fixed A record in the config file (and not a CNAME record which is only written when the node has a non-ip-based hostname) A workaround is to actually rename your node to something not IP-based.

- The other problem (dhcpd: Can't create new lease file: Permission denied) is something I've never seen and needs investigation. I don't think that changing the permissions of /var/lib/maas/dhcp will solve the problem. The DHCP server that MAAS manages is setup exactly the same way that the default dhcp is setup (the one which has its lease files in /var/lib/dhcp). The fact that you're seeing this problem only once leads me to think that this happens when the DHCP server rewrites the dhcp lease file.

Here is a extract from the DHCP server documentation:
"""
The lease file is rewritten occasionally to prevent excessive file growth. A temporary file is created containing the current lease file, the last file is renamed with a ~ suffix (e.g. /var/lib/dhcpd/dhcpd.leases~), then the temporary file is renamed to the configured lease file name.
"""
I suspect that the temporary file is written in /var/lib/dhcpd/ and that something prevents that file from being written. Maybe the current apparmor profile is too restrictive (http://paste.ubuntu.com/1297105/). Thiago, do you see apparmor-related errors in the logs around the time the dhcp error pops up?