我有一台戴尔笔记本电脑，在单个 320GB 硬盘上运行单个操作系统 Ubuntu Mate 15.10 和 GRUB，分区为/& /home。我想将默认 grub 启动延迟从 10 秒减少到最好是“0”。到目前为止，我尝试了其他地方建议的以下调整，无论是通过 Grub-Customizer 还是通过直接编辑，都没有成功。其他行保持不变。更改后，我每次/etc/default/grub都运行。Grub 启动延迟保持不变，为 10 秒。sudo update-grub
GRUB_TIMEOUT=”0”&GRUB_HIDDEN_TIMEOUT=”0”GRUB_TIMEOUT=”0”&#GRUB_HIDDEN_TIMEOUT=”0”GRUB_TIMEOUT=”0”&GRUB_HIDDEN_TIMEOUT=””GRUB_TIMEOUT=”2”&GRUB_HIDDEN_TIMEOUT=”2”
请您建议如何解决此问题。谢谢。
我的新代码（经过建议的更改）/boot/grub/grub.cfg 的代码
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#
### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
set have_grubenv=true
load_env
fi
if [ "${next_entry}" ] ; then
set default="${next_entry}"
set next_entry=
save_env next_entry
set boot_once=true
else
set default="Ubuntu"
fi
if [ x"${feature_menuentry_id}" = xy ]; then
menuentry_id_option="--id"
else
menuentry_id_option=""
fi
export menuentry_id_option
if [ "${prev_saved_entry}" ]; then
set saved_entry="${prev_saved_entry}"
save_env saved_entry
set prev_saved_entry=
save_env prev_saved_entry
set boot_once=true
fi
function savedefault {
if [ -z "${boot_once}" ]; then
saved_entry="${chosen}"
save_env saved_entry
fi
}
function recordfail {
set recordfail=1
if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi
}
function load_video {
if [ x$feature_all_video_module = xy ]; then
insmod all_video
else
insmod efi_gop
insmod efi_uga
insmod ieee1275_fb
insmod vbe
insmod vga
insmod video_bochs
insmod video_cirrus
fi
}
if [ x$feature_default_font_path = xy ] ; then
font=unicode
else
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
else
search --no-floppy --fs-uuid --set=root a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
fi
font="/usr/share/grub/unicode.pf2"
fi
if loadfont $font ; then
set gfxmode=auto
load_video
insmod gfxterm
set locale_dir=$prefix/locale
set lang=en_US
insmod gettext
fi
terminal_output gfxterm
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
else
search --no-floppy --fs-uuid --set=root a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
fi
insmod gfxmenu
insmod png
set theme=($root)/boot/grub/themes/ubuntu-mate/theme.txt
export theme
if [ "${recordfail}" = 1 ] ; then
set timeout=30
else
if [ x$feature_timeout_style = xy ] ; then
set timeout_style=hidden
set timeout=0
# Fallback hidden-timeout code in case the timeout_style feature is
# unavailable.
elif sleep --interruptible 0 ; then
set timeout=0
fi
fi
### END /etc/grub.d/00_header ###
### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=white/black
set menu_color_highlight=black/light-gray
if background_color 60,59,55; then
clear
fi
color_normal=light-gray/black
if [ -e ${prefix}/themes/ubuntu-mate/theme.txt ]; then
insmod png
theme=${prefix}/themes/ubuntu-mate/theme.txt
fi
### END /etc/grub.d/05_debian_theme ###
### BEGIN /etc/grub.d/10_linux ###
function gfxmode {
set gfxpayload="${1}"
if [ "${1}" = "keep" ]; then
set vt_handoff=vt.handoff=7
else
set vt_handoff=
fi
}
if [ "${recordfail}" != 1 ]; then
if [ -e ${prefix}/gfxblacklist.txt ]; then
if hwmatch ${prefix}/gfxblacklist.txt 3; then
if [ ${match} = 0 ]; then
set linux_gfx_mode=keep
else
set linux_gfx_mode=text
fi
else
set linux_gfx_mode=text
fi
else
set linux_gfx_mode=keep
fi
else
set linux_gfx_mode=text
fi
export linux_gfx_mode
menuentry 'Ubuntu' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-a2bdc1a5-f2fb-489d-adec-ba5a92514f0c' {
recordfail
load_video
gfxmode $linux_gfx_mode
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
else
search --no-floppy --fs-uuid --set=root a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
fi
linux /boot/vmlinuz-4.2.0-17-generic root=UUID=a2bdc1a5-f2fb-489d-adec-ba5a92514f0c ro quiet splash $vt_handoff
initrd /boot/initrd.img-4.2.0-17-generic
}
submenu 'Advanced options for Ubuntu' $menuentry_id_option 'gnulinux-advanced-a2bdc1a5-f2fb-489d-adec-ba5a92514f0c' {
menuentry 'Ubuntu, with Linux 4.2.0-17-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.2.0-17-generic-advanced-a2bdc1a5-f2fb-489d-adec-ba5a92514f0c' {
recordfail
load_video
gfxmode $linux_gfx_mode
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
else
search --no-floppy --fs-uuid --set=root a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
fi
echo 'Loading Linux 4.2.0-17-generic ...'
linux /boot/vmlinuz-4.2.0-17-generic root=UUID=a2bdc1a5-f2fb-489d-adec-ba5a92514f0c ro quiet splash $vt_handoff
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-4.2.0-17-generic
}
menuentry 'Ubuntu, with Linux 4.2.0-16-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-4.2.0-16-generic-advanced-a2bdc1a5-f2fb-489d-adec-ba5a92514f0c' {
recordfail
load_video
gfxmode $linux_gfx_mode
insmod gzio
if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
else
search --no-floppy --fs-uuid --set=root a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
fi
echo 'Loading Linux 4.2.0-16-generic ...'
linux /boot/vmlinuz-4.2.0-16-generic root=UUID=a2bdc1a5-f2fb-489d-adec-ba5a92514f0c ro quiet splash $vt_handoff
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-4.2.0-16-generic
}
}
### END /etc/grub.d/10_linux ###
### BEGIN /etc/grub.d/20_linux_xen ###
### END /etc/grub.d/20_linux_xen ###
### BEGIN /etc/grub.d/20_memtest86+ ###
menuentry 'Memory test (memtest86+)' {
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
else
search --no-floppy --fs-uuid --set=root a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
fi
knetbsd /boot/memtest86+.elf
}
menuentry 'Memory test (memtest86+, serial console 115200)' {
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
else
search --no-floppy --fs-uuid --set=root a2bdc1a5-f2fb-489d-adec-ba5a92514f0c
fi
linux16 /boot/memtest86+.bin console=ttyS0,115200n8
}
### END /etc/grub.d/20_memtest86+ ###
### BEGIN /etc/grub.d/30_os-prober ###
### END /etc/grub.d/30_os-prober ###
### BEGIN /etc/grub.d/30_uefi-firmware ###
### END /etc/grub.d/30_uefi-firmware ###
### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries. Simply type the
# menu entries you want to add after this comment. Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###
### BEGIN /etc/grub.d/41_custom ###
if [ -f ${config_directory}/custom.cfg ]; then
source ${config_directory}/custom.cfg
elif [ -z "${config_directory}" -a -f $prefix/custom.cfg ]; then
source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###
答案1
Grub 忽略零超时并设置为 10 秒
在您的系统中，/etc/default/grub您传递的是值“0”。Grub 会忽略零超时并将值重置为 10。要“欺骗”Grub，请传递值 0.0，但 Grub 测试时该值不等于 0。
将超时设置为零
在我的系统中/etc/default/grub，我设置了以下相关的线路：
#GRUB_DEFAULT=0 # Rather than option #1, we'll always default to last boot choice.
GRUB_DEFAULT=saved
GRUB_SAVEDEFAULT=true
GRUB_HIDDEN_TIMEOUT=0.0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=0.0
我使用不带双引号的值0.0来反映数值的使用方式。
注意第一行被注释掉了。这意味着 grub 不再默认为第一个菜单选项（在我的情况下是 Kernel 4.9.21），而是最后一个启动的选项（在我的情况下是 Kernel 4.4.0-72-generic，来自高级选项菜单）
第二行和第三行确保您始终启动到上次选择的相同选项。
未出现菜单时更改启动选项
更好的方法是减少超时并提供强制菜单出现的选项。此方法如下所述：如何隐藏我的 GRUB 菜单，并让 Shift 或 esc 键在启动时显示隐藏的 GRUB 菜单
答案2
搜索/boot/grub/grub.conf字符串：
set timeout=10
如果你找到了它，周围的线条可能会帮助你找出问题所在。
编者注：最好不要/boot/grub/grub.conf手动编辑，因为它会时不时地被自动覆盖。