!!!CentOs7 Grub2
[CentOS][Linux]

!!デフォルト起動OSを変更する
*http://enakai00.hatenablog.com/entry/2015/11/27/152442
!起動OSの確認
 # grep "^menuentry" /boot/grub2/grub.cfg | cut -d "'" -f2
 CentOS Linux (3.10.0-229.20.1.el7.x86_64) 7 (Core)
 CentOS Linux (3.10.0-229.20.1.el7.x86_64) 7 (Core) with debugging
 CentOS Linux (3.10.0-229.11.1.el7.x86_64) 7 (Core)
 CentOS Linux (3.10.0-229.11.1.el7.x86_64) 7 (Core) with debugging
 CentOS Linux 7 (Core), with Linux 3.10.0-229.el7.x86_64
 CentOS Linux 7 (Core), with Linux 0-rescue-4b00eec6f028470db654c2536ac2fc83
 menuentry "Windows 10"{
!現在のデフォルト起動
 # grub2-editenv list
 saved_entry=CentOS Linux (3.10.0-229.20.1.el7.x86_64) 7 (Core)
!変更
 # grub2-set-default 6
 # head -2 /boot/grub2/grubenv
 # GRUB Environment Block
 saved_entry=6
サーバー再起動