Centos 修改开机启动项顺序，开机启动列表

服务器断电后，重启时多出来了3个启动项，而之前的开机启动项在最后一个，

导致今天启动的时候 出现莫名其妙的错误,仔细查看才发现,默认启动项变了

查看 启动列表

whereis grub.cfg

[root@a172-230-240-11 ~]# whereis grub.cfg
grub: /usr/lib/grub /etc/grub.d /usr/share/grub

sudo cat /etc/grub2-efi.cfg |grep menuentry
出现下边结果

if [ x"${feature_menuentry_id}" = xy ]; then
  menuentry_id_option="--id"
  menuentry_id_option=""
export menuentry_id_option
menuentry 'CentOS Linux (3.10.0-1062.18.1.el7.x86_64) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-514.el7.x86_64-advanced-954dc937-5060-4003-8b2b-a7d94e47e9ac' {
menuentry 'CentOS Linux (3.10.0-957.21.3.el7.x86_64) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-514.el7.x86_64-advanced-954dc937-5060-4003-8b2b-a7d94e47e9ac' {
menuentry 'CentOS Linux (3.10.0-693.11.1.el7.x86_64) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-514.el7.x86_64-advanced-954dc937-5060-4003-8b2b-a7d94e47e9ac' {
menuentry 'CentOS Linux (3.10.0-514.el7.x86_64) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-514.el7.x86_64-advanced-954dc937-5060-4003-8b2b-a7d94e47e9ac' {
menuentry 'CentOS Linux (0-rescue-17db0ddeb7ba4effa7abdd39389a0e0e) 7 (Core)' --class centos --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-0-rescue-17db0ddeb7ba4effa7abdd39389a0e0e-advanced-954dc937-5060-4003-8b2b-a7d94e47e9ac' {

查看当前默认启动项

sudo grub2-editenv list

结果如下

saved_entry=CentOS Linux (3.10.0-957.27.2.el7.x86_64) 7 (Core)
果然启动项变成3.10.0的内核了

修改启动地址

sudo grub2-set-default 'CentOS Linux (5.2.1-1.el7.elrepo.x86_64) 7 (Core)'

再次查看

sudo grub2-editenv list

saved_entry=CentOS Linux (5.2.1-1.el7.elrepo.x86_64) 7 (Core)
重启以后就会发现 默认项是第一个了