Linux下如何调整根目录的空间大小
一、目的
在使用CentOS6.3版本Linux系统的时候,发现根目录(/)的空间不是很充足,而其他目录空间有很大的空闲,所以本文主要是针对现在已有的空间进行调整。首先,先来查看一下系统的空间分配情况:
[root@CentOS-78/]#df-h FilesystemSizeUsedAvailUse%Mountedon /dev/mapper/vg_centos-lv_root 50G14G34G30%/ tmpfs1.9G01.9G0%/dev/shm /dev/sda1485M37M423M8%/boot /dev/mapper/vg_centos-lv_home 404G670M382G1%/home
下面的详细步骤部分将从vg_centos-lv_home分区下取出100G的空间添加到/vg_centos-lv_root分区上去。
二、详细步骤
1、卸载vg_centos-lv_home分区
[root@CentOS-78/]#umount/home
此时在用df命令查看将会发现/home目录已经看不见了,如下所示:
[root@CentOS-78/]#df-h FilesystemSizeUsedAvailUse%Mountedon /dev/mapper/vg_centos-lv_root 50G14G34G30%/ tmpfs1.9G01.9G0%/dev/shm /dev/sda1485M37M423M8%/boot
2、从新设定vg_home-lv_home的大小
[root@CentOS-78/]#resize2fs-p/dev/mapper/vg_centos-lv_home282G resize2fs1.41.12(17-May-2010) Pleaserun'e2fsck-f/dev/mapper/vg_centos-lv_home'first.
这一步设定vg_home-lv_home大小没有成功,系统提示我们先运行下面的命令,操作如下:
[root@CentOS-78/]#e2fsck-f/dev/mapper/vg_centos-lv_home e2fsck1.41.12(17-May-2010) Pass1:Checkinginodes,blocks,andsizes Pass2:Checkingdirectorystructure Pass3:Checkingdirectoryconnectivity Pass4:Checkingreferencecounts Pass5:Checkinggroupsummaryinformation /dev/mapper/vg_centos-lv_home:1386/26836992files(0.9%non-contiguous),1855856/107344896blocks
从新设定vg_home-lv_home的大小:
[root@CentOS-78/]#resize2fs-p/dev/mapper/vg_centos-lv_home282G resize2fs1.41.12(17-May-2010) Resizingthefilesystemon/dev/mapper/vg_centos-lv_hometo73924608(4k)blocks. Beginpass2(max=43) RelocatingblocksXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Beginpass3(max=3276) ScanninginodetableXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Beginpass4(max=266) UpdatinginodereferencesXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Thefilesystemon/dev/mapper/vg_centos-lv_homeisnow73924608blockslong.
检查是否成功:
[root@CentOS-78/]#mount/home [root@CentOS-78/]# [root@CentOS-78/]#df-h FilesystemSizeUsedAvailUse%Mountedon /dev/mapper/vg_centos-lv_root 50G14G34G30%/ tmpfs1.9G01.9G0%/dev/shm /dev/sda1485M37M423M8%/boot /dev/mapper/vg_centos-lv_home 278G663M263G1%/home [root@CentOS-78/]#
3、将lv_home逻辑分区减小到指定大小
[root@CentOS-78/]#lvreduce-L282G/dev/mapper/vg_centos-lv_home WARNING:Reducingactiveandopenlogicalvolumeto282.00GiB THISMAYDESTROYYOURDATA(filesystemetc.) Doyoureallywanttoreducelv_home?[y/n]:y Reducinglogicalvolumelv_hometo282.00GiB Logicalvolumelv_homesuccessfullyresized [root@CentOS-78/]#
我认为这个命令是将已经减少的100G空间拿到系统公共的区域,可以被其他分区加载和利用。
查询卷组的信息:
[root@CentOS-78/]#vgdisplay ---Volumegroup--- VGNamevg_centos SystemID Formatlvm2 MetadataAreas1 MetadataSequenceNo5 VGAccessread/write VGStatusresizable MAXLV0 CurLV3 OpenLV3 MaxPV0 CurPV1 ActPV1 VGSize465.27GiB PESize4.00MiB TotalPE119109 AllocPE/Size86472/337.78GiB FreePE/Size32637/127.49GiB VGUUID1k4ooN-RFV9-uyf1-uMYf-aERG-YaGs-ZNoSD6
FreePE/Size指定的应该是现在可在分配的空间。
4、增加vg_centos-lv_root分区的大小
将可用的空间添加到vg_centos-lv_root分区上面:
[root@CentOS-78/]#lvextend-L+127.40G/dev/mapper/vg_centos-lv_root Roundingupsizetofullphysicalextent127.40GiB Extendinglogicalvolumelv_rootto177.40GiB Logicalvolumelv_rootsuccessfullyresized [root@CentOS-78/]#
从新设定该分区的大小:
[root@CentOS-78/]#resize2fs-p/dev/mapper/vg_centos-lv_root resize2fs1.41.12(17-May-2010) Filesystemat/dev/mapper/vg_centos-lv_rootismountedon/;on-lineresizingrequired olddesc_blocks=4,new_desc_blocks=12 Performinganon-lineresizeof/dev/mapper/vg_centos-lv_rootto46504960(4k)blocks. Thefilesystemon/dev/mapper/vg_centos-lv_rootisnow46504960blockslong.
5、再次查看分区大小
[root@CentOS-78/]#df-h FilesystemSizeUsedAvailUse%Mountedon /dev/mapper/vg_centos-lv_root 175G14G153G9%/ tmpfs1.9G01.9G0%/dev/shm /dev/sda1485M37M423M8%/boot /dev/mapper/vg_centos-lv_home 278G663M263G1%/home
我们发现vg_centos-lv_root分区的空间已经增加了125G,之所以比lv_home减少的空间要多25G主要是由于我们把系统所有的可用的空间都加在了lv_root分区。
三、所遇到的问题
1、在卸载/home目录的时候失败
可先执行如下fuser命令,然后再umount即可:
[root@CentOS-78/]#fuser-m/home [root@CentOS-78/]#
2、设定完lv_home的大小,再次mount该分区时,发现用df命令无法看到给分区,此时只要在mount一次即可
3、在设定lv_root的大小时,不要把FreePE/Size的空间全部都用上,这很可能会出现FreePE空间不足的现象,建议保留一点FreePE的空间。
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持毛票票。