关于linux lvm ext2onlie命令

一、关于resize功能

1、ext2/ext3要resize，一般都使用resize2fs。
2、对于已mount的文件系统，只能扩大。
3、在早期的RHEL中，由于resize2fs无在线resize功能，故额外提供了ext2online。
   kernel 2.6以后，resize2fs已实现在线resize功能。
4、只有ext3可以在线扩展。
5、ext2online与resize2fs均可离线resize ext2和ext3(可以看看manpage)。

二、关于ext2online的命名

由于ext3fs=ext2fs+journaling，所以指令取名为ext2*，并不是说就只能用于ext2，它既可用于ext2，也可用于ext3。类似命名指令还有e2fsck，e2label等。

三、ext2online工具的安装

rpm包下载地址：

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1、创建sct用户
#useradd sct
2、安装ext2resize包
#rpm -ivh ext2resize-1.1.19-1.x86_64.rpm
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安装完成后会有三个命令：
ext2online   ext2prepare  ext2resize
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注意：安装此工具，必须有sct用户(当前用户不用是sct)
否则将出现如下错误：

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[root@rhel15 ~]# rpm -ivh ext2resize-1.1.19-1.x86_64.rpm
Preparing...                ########################################### [100%]
   1:ext2resize             warning: user sct does not exist - using root
warning: group sct does not exist - using root
warning: user sct does not exist - using root 22%)
warning: group sct does not exist - using root
warning: user sct does not exist - using root 47%)
warning: group sct does not exist - using root
warning: user sct does not exist - using root 78%)
warning: group sct does not exist - using root
warning: user sct does not exist - using root
warning: group sct does not exist - using root
warning: user sct does not exist - using root
warning: group sct does not exist - using root
warning: user sct does not exist - using root 88%)
warning: group sct does not exist - using root
warning: user sct does not exist - using root 91%)
warning: group sct does not exist - using root
warning: user sct does not exist - using root 92%)
warning: group sct does not exist - using root
warning: user sct does not exist - using root
warning: group sct does not exist - using root
warning: user sct does not exist - using root
warning: group sct does not exist - using root
warning: user sct does not exist - using root 96%)
warning: group sct does not exist - using root
warning: user sct does not exist - using root 97%)
warning: group sct does not exist - using root
warning: user sct does not exist - using root
warning: group sct does not exist - using root
########################################### [100%]

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