通过安装rac 10g for redhat as 4与rac 10g for redhat as 5发现配置裸设备的自启动不同下面列出两种版本下的配置1.linux redhat
通过安装rac 10g for RedHat as 4与rac 10g for redhat as 5发现配置裸设备的自启动不同
下面列出两种版本下的配置
1.linux redhat as 4
Edit the /etc/sysconfig/rawdevices file, adding the following lines. (增加裸设备映射)
/dev/raw/raw1 /dev/sdb1
/dev/raw/raw2 /dev/sdc1
//改变裸设备拥有者和组
chown Oracle:oinstall /dev/raw/raw1
chown oracle:oinstall /dev/raw/raw2
//改变设备访问权限
chmod 600 /dev/raw/raw1
chmod 600 /dev/raw/raw2
修改/etc/udev/permissions.d/50-udev.permissions,
[root@rac1 ~]# vi /etc/udev/permissions.d/50-udev.permissions
# raw devices
ram*:root:disk:0660
#raw/*:root:disk:0660
raw/*:oracle:dba:0660 机器启动时能自动加载给oracle用户使用。
2.linux redhat as 5
因为rh5中取消了rawdevices服务,要使用裸设备的话,需要做以下配置。
[root@raw1 ~]#vi /etc/udev/rules.d/60-raw.rules
添加以下部分的内容
ACTION=="add", KERNEL=="sdb1", RUN+="/bin/raw /dev/raw/raw1 %N"
-r9El:h'KDp3u0ACTION=="add", ENV{MAJOR}=="8", ENV{MINOR}=="1", RUN+="/bin/raw /dev/raw/raw2 %M %m"
//然后运行启动设备命令
[root@raw1 ~]# start_udev
starting udev: [ OK ]
补充:
今天遇到了个问题,就是做ASM实例的时候用的一个硬盘,分成2个分区安装ASM的时候,ACTION=="add", ENV{MAJOR}=="8", ENV{MINOR}=="1", RUN+="/bin/raw /dev/raw/raw2 %M %m" 这里面的ENV{MINOR}=="1" 设置不对的情况下启动不了裸设备,如何正确设置呢?
突然想起来,裸设备支持到255个,每个硬盘16个分区,那么我挂载的是一个硬盘,在这个硬盘上分了3个分区,那么从设备号就是17,18,19,如何看从设备分区号呢,也可以通过这样查看,,进到DEV查看:ll /dev/* 看到你的分区的属性里有 8 17,8 18的字样即是了,想想大多数文档里做RAC的时候,都是采用3个虚拟机硬盘实现的,再设置的时候都是以 17,33,49 这样的从设备号进行配置的和挂载硬盘的,更加确认了我的思路。

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