Скрипт для исправления проблем в Ubuntu GRUB в 1 клик.

#!/bin/sh

load_default_grub() {
    . /etc/default/grub
}

get_yes_no() {
    while [ true ]; do
        echo -n "$1 (Y/N) ? "
        read a
        echo
        if [ $? != 0 ]; then
            a='No'; return;
        fi
        case $a in
            [Yy][Ee][Ss]|[Yy]) a='Yes'; return;;
            [Nn][Oo]|[Nn]) a='No'; return;;
            *) ;;
        esac
    done
}

# Load config and uncomment variable.
load_default_grub
if (grep -qwai '^#GRUB_DISABLE_RECOVERY=' /etc/default/grub >/dev/null); then
    echo 'INFO: Uncomment the GRUB_DISABLE_RECOVERY variable.'
    sed -i 's/^#GRUB_DISABLE_RECOVERY=\(.*\)/GRUB_DISABLE_RECOVERY=\1/' /etc/default/grub
fi
# Load config again, check value and set if need.
load_default_grub
if [ "$GRUB_DISABLE_RECOVERY" != 'true' ]; then
    if [ -z "$GRUB_DISABLE_RECOVERY" ]; then
        echo 'INFO: Add GRUB_DISABLE_RECOVERY="true"'
        echo 'GRUB_DISABLE_RECOVERY="true"' >> /etc/default/grub
    else
        echo 'INFO: Set GRUB_DISABLE_RECOVERY to "true"'
        sed -i 's/^GRUB_DISABLE_RECOVERY=.*/GRUB_DISABLE_RECOVERY="true"/' /etc/default/grub
    fi
fi

# Delete deprecated options GRUB_HIDDEN_TIMEOUT*.
if (grep -qwai '^GRUB_HIDDEN_TIMEOUT.*' /etc/default/grub >/dev/null); then
    echo 'INFO: Delete deprecated options GRUB_HIDDEN_TIMEOUT*'
    sed -i '/^GRUB_HIDDEN_TIMEOUT.*/d' /etc/default/grub
fi

# Add option GRUB_RECORDFAIL_TIMEOUT=15 for automatic boot on fail.
if ! (grep -qwai '^GRUB_RECORDFAIL_TIMEOUT=.*' /etc/default/grub >/dev/null); then
    echo 'INFO: Add option GRUB_RECORDFAIL_TIMEOUT=15 for automatic boot on fail.'
    echo 'GRUB_RECORDFAIL_TIMEOUT=15' >> /etc/default/grub
fi


# GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
if (grep -qwai '^GRUB_CMDLINE_LINUX_DEFAULT=.*' /etc/default/grub >/dev/null); then
    # Load config again, check value and set if need.
    load_default_grub
    for i in $GRUB_CMDLINE_LINUX_DEFAULT; do
        case "$i" in
            'splash') i='nosplash' ;;
            'quiet') i='noquiet' ;;
        esac
        if [ -n "$GRUB_CMDLINE_LINUX_DEFAULT_OUT" -a -n "$i" ]; then
            GRUB_CMDLINE_LINUX_DEFAULT_OUT="$GRUB_CMDLINE_LINUX_DEFAULT_OUT $i"
        else
            GRUB_CMDLINE_LINUX_DEFAULT_OUT="$i"
        fi
    done
    sed -i -e "s/^GRUB_CMDLINE_LINUX_DEFAULT=.*/GRUB_CMDLINE_LINUX_DEFAULT=\"$GRUB_CMDLINE_LINUX_DEFAULT_OUT\"/" /etc/default/grub
fi

# Finnaly re-generate grub.cfg.
get_yes_no "Do you want to run update-grub"
[ $a = 'Yes' ] && update-grub