学习环境下Oracle RAC中的CentOS系统BUG解决
在工作期间利用三台破PC机器很老很老的那种，搭建了一个RAC的学习环境很是欣喜不已，这嘛，既利用了废旧硬件，也为自己创造了学习环境，一举多得，当然高兴了哈！
一台主机中的时候报告了错误，如下图：
心想这下子玩完了。
于是重启系统，大约过了一分钟后，登录系统，，没什么问题，，不一会儿就又出现了上面的问题。
这么久了还没见过linux崩溃过（除了在一台Dell 750的机器上安装CentOS 5.2，硬件不支持，害我重做了两遍系统！）
这是怎么回事儿呢？？ 在伟大的google中寻找答案，无果。
这时候想这系统安装的时候没有升级，就升级一下系统算了，大不了重来！
yum upgrade 升级开始，一下子有185个软件包需要更新，包括内核。
在这里一开始运行yum是在3级别下面，可是不行，yum 在安装更新的时候报告错误，无法安装，这个时候有点沉不住气了哦：（
于是init4 在这个级别安装，还是不行，再试 init2 也不行
重启下系统在正常模式下安装，在安装的时候光标总在那闪，没有反应。
这次直接进入到yum下载的软件目录中 rpm -ivh kernel-* 只安装了新的内核
成功安装后，重启系统。
其中一个节点RAC2的内核 Linux rac2.andylhz.com 2.6.9-100.EL #1 Fri Feb 18 01:29:32 EST 2011 i686 i686 i386 GNU/Linux
要比节点RAC1高：Linux rac1.andylhz.com 2.6.9-89.EL #1 Mon Jun 22 12:19:40 EDT 2009 i686 i686 i386 GNU/Linux
在预料之中的事情发生了-asmlib 驱动无法启动！ 为什么呢？因为OracleASM 的版本和新的内核不匹配，所以无法加载
Mar 28 13:01:17 rac2 modprobe: FATAL: Module oracleasm not found.
Mar 28 13:01:17 rac2 oracleasm: Unable failed
Mar 28 13:02:06 rac2 modprobe: FATAL: Module oracleasm not found.
Mar 28 13:02:06 rac2 oracleasm: Unable failed
Mar 28 13:02:09 rac2 modprobe: FATAL: Module oracleasm not found.
Mar 28 13:02:09 rac2 oracleasm: Unable failed
Mar 28 13:02:21 rac2 modprobe: FATAL: Module oracleasm not found.
Mar 28 13:02:21 rac2 oracleasm: Unable failed
Mar 28 13:07:23 rac2 modprobe: FATAL: Module oracleasm not found.
这个时候尝试下载匹配的ASMlib 重新安装后 重新配置oracleasm 识别了之前asm磁盘
Mar 28 13:13:21 rac2 oracleasm: succeeded
Mar 28 13:13:25 rac2 oracleasm: succeeded
Mar 28 13:16:26 rac2 oracleasm: succeeded
Mar 28 13:16:29 rac2 oracleasm: succeeded
RAC已经成功恢复！
从昨天更新内核到现在没有再出现图中的错误！ 所以有时候及时更新内核是很有必要的！
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