Comment 1 for bug 1470400

This is the error message

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Creating config file /etc/default/grub with new version
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?).
dpkg: error processing package grub-efi-amd64 (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of grub-efi-amd64-signed:
 grub-efi-amd64-signed depends on grub-efi-amd64 (= 2.02~beta2-9ubuntu1.3); however:
  Package grub-efi-amd64 is not configured yet.

dpkg: error processing package grub-efi-amd64-signed (--configure):
 dependency problems - leaving unconfigured
/bin/df: cannot read table of mounted file systems: No such file or directory
No apport report written because the error message indicates its a followup error from a previous failure.
Errors were encountered while processing:
 grub-efi-amd64
 grub-efi-amd64-signed
E: Sub-process /usr/bin/dpkg returned an error code (1)
install failed with error Reading package lists...

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