RHEL 升級內核和回退步驟

目標：將內核從RHEL 6.8自帶的2.6.32-642升級到2.6.32-754.23.1

從redhat官網上下載內核kernel和kernel-firmware

將軟件包上傳到linux

[root@oracle ~]# yum install kernel-2.6.32-754.23.1.el6.x86_64.rpm kernel-firmware-2.6.32-754.23.1.el6.noarch.rpm 

 

推薦使用yum升級

 

 

然後修改默認的啓動內核

[root@oracle ~]# vim /etc/grub.conf

[root@oracle ~]# vim /etc/grub.conf

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE:  You have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /boot/, eg.
#          root (hd0,0)
#          kernel /vmlinuz-version ro root=/dev/mapper/vg_oracle-lv_root
#          initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux Server (2.6.32-754.23.1.el6.x86_64)
        root (hd0,0)
        kernel /vmlinuz-2.6.32-754.23.1.el6.x86_64 ro root=/dev/mapper/vg_oracle-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_LVM_LV=vg_oracle/lv_root rd_NO_MD rd_LVM_LV=vg_oracle/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto  KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet elevator=deadline
        initrd /initramfs-2.6.32-754.23.1.el6.x86_64.img
title Red Hat Enterprise Linux 6 (2.6.32-642.el6.x86_64)
        root (hd0,0)
        kernel /vmlinuz-2.6.32-642.el6.x86_64 ro root=/dev/mapper/vg_oracle-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_LVM_LV=vg_oracle/lv_root rd_NO_MD rd_LVM_LV=vg_oracle/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto  KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet elevator=deadline
        initrd /initramfs-2.6.32-642.el6.x86_64.img

default=0表示默認的啓動內核是第一個，也就是新安裝的2.6.32-754.23.1

然後重啓服務器，確認新內核是第一位，並從新內核正常啓動。

卸載：

假如發現新內核不合適，那麼需要切換到舊內核，使用yum卸載

[root@oracle ~]# rpm -qa |grep kernel
kernel-devel-2.6.32-642.el6.x86_64
dracut-kernel-004-409.el6.noarch
kernel-2.6.32-642.el6.x86_64
kernel-headers-2.6.32-642.el6.x86_64
kernel-2.6.32-754.23.1.el6.x86_64
abrt-addon-kerneloops-2.0.8-40.el6.x86_64
kernel-firmware-2.6.32-754.23.1.el6.noarch
libreport-plugin-kerneloops-2.0.9-32.el6.x86_64
[root@oracle ~]# yum remove kernel-2.6.32-754.23.1.el6.x86_64 kernel-firmware-2.6.32-754.23.1.el6.noarch

 然後從本地yum源中重新安裝kernel-firmware

[root@oracle ~]# yum install kernel-firmware kernel

再次重啓，發現默認內核回去了，並且/etc/grub.conf 變回去了