centos5.5 内核升级

当前系统版本为CentOS 5.5,内核版本为2.6.18-194，现将内核升级到2.6.35.4

[[email protected] data]# wget http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.35.4.tar.bz2
[[email protected] data]# tar -jxvf linux-2.6.35.4.tar.bz2
[[email protected] data]# mv linux-2.6.35.4 /usr/src
[[email protected] data]# cd /usr/src/linux-2.6.35.4
#配置内核参数，选择自己所需的模块
[[email protected] linux-2.6.35.4]# make menuconfig
#编译安装内核
[[email protected] linux-2.6.35.4]# make
[[email protected] linux-2.6.35.4]# make modules
[[email protected] linux-2.6.35.4]# make modules_install
[[email protected] linux-2.6.35.4]# make install

#修改默认以新的内核启动。
[[email protected] linux-2.6.35.4]# vi /boot/grub/grub.conf
default=0
#将新的内核配置文件复制到/boot目录。
[[email protected] linux-2.6.35.4]# cp /usr/src/linux-2.6.35.4/.config /boot/config-2.6.35.4
[[email protected] linux-2.6.35.4]# reboot

#重启后验证内核版本
[[email protected] /]# uname -r
2.6.35.4

#升级过程中遇到的问题
一、启动报错
mount: could not find filesystem ‘/dev/root’
setuproot: moving /dev failed: No such file or directory
setuproot: error mounting /proc: No such file or directory
setuproot: error mounting /sys: No such file or directory
switchroot: mount failed: No such file or directory
Kernel panic – not syncing: Attempted to kill init!

解决方法：
执行完make menuconfig后，修改/usr/src/linux-2.6.35.4/.config
将#CONFIG_SYSFS_DEPRECATED_V2 is not set
默认被注释掉的，将其改为y。即修改为
CONFIG_SYSFS_DEPRECATED_V2=y
再接着编译安装内核

二、启动报错
insmod: error inserting '/lib/dm-region-hash.ko' : -1 File exists

解决方法：
1、解压initrd文件
[[email protected] ~]# cp /boot/initrd-2.6.35.4.img /tmp
[[email protected] ~]# cd /tmp/
[[email protected] tmp]# ls
initrd-2.6.35.4.img
[[email protected] tmp]# mkdir newinitrd
[[email protected] tmp]# cd newinitrd/
[[email protected] newinitrd]# zcat ../initrd-2.6.35.4.img |cpio -i
11282 blocks
释放之后看到如下内容
[[email protected] newinitrd]# ls
bin   dev   etc   init   lib   proc   sbin   sys   sysroot

2、下边就是编辑init，删掉其中重复的四行中的两行
echo "Loading dm-region-hash.ko module"
insmod /lib/dm-region-hash.ko
echo "Loading dm-region-hash.ko module"
insmod /lib/dm-region-hash.ko

3、重新打包initrd
[[email protected] newinitrd]# find .|cpio -c -o > ../initrd
11282 blocks
[[email protected] newinitrd]# cd ..
[[email protected] tmp]# gzip -9 < initrd > initrd.img
[[email protected] tmp]# ls
initrd-2.6.35.4.img    initrd    initrd.img          newinitrd

initrd.img就是重新打包的initrd了，然后把initrd.img拷贝到/boot
[[email protected] tmp]# mv /boot/initrd-2.6.35.4.img /boot/initrd-2.6.35.4.img.bak
[[email protected] tmp]# mv initrd.img /boot/initrd-2.6.35.4.img
[[email protected] tmp]# reboot
这样“insmod: error inserting '/lib/dm-region-hash.ko' : -1 File exists” 就不会有了