VM element: /usr/sbin/grub2-install: error: will not proceed with blocklists.

[Lucas Alvares Gomes]

Building an image on a Fedora 22 host, when installing the GRUB2 bootloader I see:

+ /usr/sbin/grub2-install '--modules=biosdisk part_msdos' /dev/loop0
Installing for i386-pc platform.
/usr/sbin/grub2-install: warning: this msdos-style partition label has no post-MBR gap; embedding won't be possible.
/usr/sbin/grub2-install: warning: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged..
/usr/sbin/grub2-install: error: will not proceed with blocklists.
/dev/loop0: [0039]:311600 (/tmp/image.uAvRGGAK/image.raw)

Workaround:

export DIB_EXTLINUX=1 so the VM element will install syslinux instead of GRUB.

Another workaround (not tested):

Apparently you can --force the grub-install command to avoid that error[1]

[1] https://wiki.archlinux.org/index.php/GRUB#Install_to_partition_or_partitionless_disk

[Dan Prince (dan-prince)]

The --force option works so I'd say lets perhaps just go with that for now.

[Dan Prince (dan-prince)]

Okay. I see. So if we use --force we'll actually be making so that subsequent updates to the core.img file potentially hose thinks. So we'd want to make it immutable to prevent that with this work around.

[Dan Prince (dan-prince)]

Perhaps also related I see this in the seed build logs on F22:

+ sudo sfdisk /dev/loop0
Re-reading the partition table failed.: Invalid argument
+ sudo partprobe /dev/loop0

[Ben Nemec (bnemec)]

I'm not sure if this is still valid, but it was a problem in dib which is no longer part of tripleo.