Non-fatal error message observed in PXE boot sequence

[Mark Shuttleworth]

While powering on a MAAS-deployed machine today I saw this:

My IP address seems to be C0A809CA 192.168.9.202
ip=192.168.9.202:192.168.9.2:192.168.9.1:255.255.255.0
BOOTIF=01-00-25-90-4c-f0-06
SYSUUID=58384454-544e-0025-904c-0025904cf006
TFTP prefix:
Trying to load: pxelinux.cfg/01-00-25-90-4c-f0-06 ok
Booting local disk ...
Booting...
error: diskfilter writes are not supported.

Press any key to continue...[ 0.000000] Initializing cgroup subsys cpuset

Any idea what "diskfilter writes" are, why the system thought they were requested, and why it worked regardless?

[Newell Jensen (newell-jensen)]

This is a known issue with grub, bug #1274320

Seems like they are still having issues with this as per the comments in the bug report.

For more background this has some good information:

http://askubuntu.com/questions/468466/diskfilter-writes-are-not-supported-what-triggers-this-error