The method of expanding the Linux root directory system with insufficient space __linux

I. Purpose

When using the CentOS6.3 version Linux system, found that the root directory (/) of the space is not sufficient, and other directory space has a lot of free, so this article is mainly for the existing space to adjust. First, let's look at the space allocation of the system:




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01.[root@centos-78/]# df-h
02.Filesystem Size Used avail use% mounted on
03./dev/mapper/vg_centos-lv_root
50G 14G 34G 30%/
05.tmpfs 1.9G 0 1.9G 0%/dev/shm
06./DEV/SDA1 485M 37M 423M 8%/boot
07./dev/mapper/vg_centos-lv_home
404G 670M 382G 1%/home
The following detailed steps section will remove 100G of space from the Vg_centos-lv_home partition and add it to the/vg_centos-lv_root partition.

Second, detailed steps

1. Uninstall Vg_centos-lv_home partition




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01.[root@centos-78/]# Umount/home
At this point in the DF command to see that the/home directory has been seen, as follows:




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01.[root@centos-78/]# df-h
02.Filesystem Size Used avail use% mounted on
03./dev/mapper/vg_centos-lv_root
50G 14G 34G 30%/
05.tmpfs 1.9G 0 1.9G 0%/dev/shm
06./DEV/SDA1 485M 37M 423M 8%/boot


2, the new set Vg_home-lv_home size




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01.[root@centos-78/]# resize2fs-p/dev/mapper/vg_centos-lv_home 282G
02.RESIZE2FS 1.41.12 (17-may-2010)
03.Please Run ' e2fsck-f/dev/mapper/vg_centos-lv_home '.
This step to set the Vg_home-lv_home size did not succeed, the system prompts us to run the following command, the operation is as follows:




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01.[root@centos-78/]# e2fsck-f/dev/mapper/vg_centos-lv_home
02.e2fsck 1.41.12 (17-may-2010)
03.Pass 1:checking inodes, blocks, and sizes
04.Pass 2:checking directory structure
05.Pass 3:checking Directory Connectivity
06.Pass 4:checking Reference counts
07.Pass 5:checking Group summary Information
08./dev/mapper/vg_centos-lv_home:1386/26836992 files (0.9% non-contiguous), 1855856/107344896 blocks
To reset the Vg_home-lv_home size:




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01.[root@centos-78/]# resize2fs-p/dev/mapper/vg_centos-lv_home 282G
02.RESIZE2FS 1.41.12 (17-may-2010)
03.Resizing the filesystem on/dev/mapper/vg_centos-lv_home to 73924608 (4k) blocks.
04.Begin Pass 2 (max = 43)
05.Relocating blocks Xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
06.Begin Pass 3 (max = 3276)
07.Scanning inode Table Xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
08.Begin Pass 4 (max = 266)
09.Updating Inode References Xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
10.The filesystem On/dev/mapper/vg_centos-lv_home is now 73924608 blocks long.
Check for success:




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01.[root@centos-78/]# Mount/home
02.[root@centos-78/]#
03.[root@centos-78/]# df-h
04.Filesystem Size Used avail use% mounted on
05./dev/mapper/vg_centos-lv_root
50G 14G 34G 30%/
07.tmpfs 1.9G 0 1.9G 0%/dev/shm
08./DEV/SDA1 485M 37M 423M 8%/boot
09./dev/mapper/vg_centos-lv_home
278G 663M 263G 1%/home
11.[root@centos-78/]#
3, reduce the lv_home logical partition to the specified size




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01.[root@centos-78/]# lvreduce-l 282g/dev/mapper/vg_centos-lv_home
Warning:reducing Active and open logical volume to 282.00 GiB
This May DESTROY YOUR DATA (filesystem etc.)
04.Do you really want to reduce lv_home? [y/n]: Y
Reducing logical volume Lv_home to 282.00 GiB
Logical Volume Lv_home successfully resized
07.[root@centos-78/]#
I think this command is to take the reduced 100G space to the system public area, can be loaded and used by other partitions.


To query the volume Group for information:




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01.[root@centos-78/]# Vgdisplay
---Volume Group---
, VG Name Vg_centos
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 5
-VG Access Read/write
-VG Status resizable
MAX LV 0
Cur LV 3
Open LV 3
Max PV 0
Cur PV 1
ACT PV 1
VG Size 465.27 GiB
PE Size 4.00 MiB
Total PE 119109
Alloc pe/size 86472/337.78 GiB
Free Pe/size 32637/127.49 GiB
VG UUID 1k4oon-rfv9-uyf1-umyf-aerg-yags-znosd6


The free pe/size designation should be now available in the allocated space.
4, increase the size of the Vg_centos-lv_root partition
Add the available space to the Vg_centos-lv_root partition:




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01.[root@centos-78/]# lvextend-l +127.40g/dev/mapper/vg_centos-lv_root
Rounding up size to full physical extent 127.40 GiB
Extending logical Volume Lv_root to 177.40 GiB
Logical Volume Lv_root successfully resized
05.[root@centos-78/]#
To reset the size of the partition:



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01.[root@centos-78/]# resize2fs-p/dev/mapper/vg_centos-lv_root
02.RESIZE2FS 1.41.12 (17-may-2010)
03.Filesystem at/dev/mapper/vg_centos-lv_root is mounted on/; On-line resizing required
04.old desc_blocks = 4, new_desc_blocks = 12
05.Performing a on-line resize of/dev/mapper/vg_centos-lv_root to 46504960 (4k) blocks.