▶ sudo dpkg --configure initramfs-tools
[sudo] password for abrahams:
Setting up initramfs-tools (0.120ubuntu6) ...
update-initramfs: deferring update (trigger activated)
Processing triggers for initramfs-tools (0.120ubuntu6) ...
ln: fatal error: -f/--auxiliary may not be used without -shared
update-initramfs: Generating /boot/initrd.img-4.2.0-16-generic
ln: error: /proc/mounts: file is empty
ln: error: cannot open /var/tmp/mkinitramfs_qXMR83/etc/mtab: No such file or directory
ln: error: cannot open busybox: No such file or directory
ln: error: cannot open /var/tmp/mkinitramfs_qXMR83/bin/sh: No such file or directory
E: /usr/share/initramfs-tools/hooks/busybox failed with return 1.
update-initramfs: failed for /boot/initrd.img-4.2.0-16-generic with 1.
dpkg: error processing package initramfs-tools (--configure):
 subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
 initramfs-tools