Add echo for each line to debug.

ubuntu/3-post-install.sh

@@ -15,34 +15,43 @@ fi # "sourced" validation
 
 ## Mount the target file system
 # /target is created by the Ubiquity installer
+echo "Mount /dev/mapper/${VGNAME}-${LVROOTNAME} on /target."
 mount /dev/mapper/${VGNAME}-${LVROOTNAME} /target
 
 # And mount other directories
+echo "Mount all other dirs."
 for n in proc sys dev etc/resolv.conf; do mount --rbind "/$n" "/target/$n"; done
 
 # Change root and create the keyfile and ramfs image for Linux kernel. 
+echo "Chroot."
 cat <<HEREDOC | chroot /target /bin/bash
 # Mount the rest of partitions by target /etc/fstab
 mount -a
 
 # Set up the kernel hook of encryption
+echo "install cryptsetup-initramfs package."
 apt install -y cryptsetup-initramfs
+echo "Register key file to the ramfs"
 echo "KEYFILE_PATTERN=/etc/luks/*.keyfile" >> /etc/cryptsetup-initramfs/conf-hook
 echo "UMASK=0077" >> /etc/initramfs-tools/initramfs.conf
 
 # Prepare a key file to embed in to the ramfs.
+echo "Prepair key file."
 mkdir /etc/luks
 dd if=/dev/urandom of=/etc/luks/boot_os.keyfile bs=4096 count=1
 chmod u=rx,go-rwx /etc/luks
 chmod u=r,go-rwx /etc/luks/boot_os.keyfile
 
 # Add a key to the key file. Use the passphrase in the environment variable. 
+echo "Add a key to the key file."
 printf %s "${PASSPHRASE}" | cryptsetup luksAddKey -d - "${DEV}${CRYPTPARTITION}" /etc/luks/boot_os.keyfile
 
 # Add the LUKS volume information to /etc/crypttab to decrypt by kernel.  
+echo "Add LUKS volume info to /etc/crypttab."
 echo "${CRYPTPARTNAME} UUID=$(blkid -s UUID -o value ${DEV}${CRYPTPARTITION}) /etc/luks/boot_os.keyfile luks,discard" >> /etc/crypttab
 
 # Finally, update the ramfs initial image with the key file. 
+echo "Upadte initramfs."
 update-initramfs -uk all
 
 # Leave chroot