扩容原因：/dev/vg_rhel64/lv_root 占用率达到100%,导致部分应用无法继续运行
操作过程：
1.关闭系统，在虚拟机中添加一块10G的磁盘
2.查看新添加磁盘对应的名称
[[email protected] ~]# fdisk -cul 得知磁盘对应名称为 /dev/sdc
3.给sdc分区，只分一个区sdc1
[[email protected] ~]# fdisk -cu /dev/sdc
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0xa655ad49.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won‘t be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First sector (2048-20971519, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519):
Using default value 20971519
Command (m for help): p
Disk /dev/sdc: 10.7 GB, 10737418240 bytes
255 heads, 63 sectors/track, 1305 cylinders, total 20971520 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xa655ad49
Device Boot Start End Blocks Id System
/dev/sdc1 2048 20971519 10484736 83 Linux
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
4.在sdc1上创建pv
[[email protected] ~]# pvcreate /dev/sdc1
Physical volume "/dev/sdc1" successfully created
5.查看pv的情况
[[email protected] ~]# pvdisplay
--- Physical volume ---
PV Name /dev/sdb2
VG Name vg_rhel64
PV Size 14.51 GiB / not usable 3.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 3714
Free PE 0
Allocated PE 3714
PV UUID VBVnoj-7R81-0BgJ-j8Tr-nq2W-i84v-xJZlqZ
--- Physical volume ---
PV Name /dev/sda5
VG Name vg_myvg
PV Size 1.00 GiB / not usable 4.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 255
Free PE 0
Allocated PE 255
PV UUID CmX1Tx-1LdX-wtRf-qXoX-Myg3-WR5g-klwUg9
--- Physical volume ---
PV Name /dev/sda6
VG Name vg_myvg
PV Size 1021.00 MiB / not usable 0
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 255
Free PE 0
Allocated PE 255
PV UUID Q9FgFp-0gHF-KMtK-Vrfa-2f95-eKRg-7bq40d
"/dev/sdc1" is a new physical volume of "10.00 GiB"
--- NEW Physical volume ---
PV Name /dev/sdc1
VG Name
PV Size 10.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID KrvMui-Kzmd-qGdP-SBl6-yYfZ-Q5Y6-PA1Vv0
6.查看系统当前vg的情况
[[email protected] ~]# vgdisplay
--- Volume group ---
VG Name vg_rhel64
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 3
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 1
Act PV 1
VG Size 14.51 GiB
PE Size 4.00 MiB
Total PE 3714
Alloc PE / Size 3714 / 14.51 GiB
Free PE / Size 0 / 0
VG UUID Yb3iGX-1SdP-MoFz-I4iS-0oDt-NhVD-SE5UAr
--- Volume group ---
VG Name vg_myvg
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 5
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 2
Act PV 2
VG Size 1.99 GiB
PE Size 4.00 MiB
Total PE 510
Alloc PE / Size 510 / 1.99 GiB
Free PE / Size 0 / 0
VG UUID x9sUhJ-gQ4c-avxR-daQ1-ceib-VtGF-nvwqv9
7.给vg扩容
[[email protected] ~]# vgextend vg_rhel64 /dev/sdc1
Volume group "vg_rhel64" successfully extended
8.查看扩容后vg的情况
[[email protected] ~]# vgdisplay
--- Volume group ---
VG Name vg_rhel64
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 4
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 2
Act PV 2
VG Size 24.50 GiB
PE Size 4.00 MiB
Total PE 6273
Alloc PE / Size 3714 / 14.51 GiB
Free PE / Size 2559 / 10.00 GiB
VG UUID Yb3iGX-1SdP-MoFz-I4iS-0oDt-NhVD-SE5UAr
--- Volume group ---
VG Name vg_myvg
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 5
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 2
Act PV 2
VG Size 1.99 GiB
PE Size 4.00 MiB
Total PE 510
Alloc PE / Size 510 / 1.99 GiB
Free PE / Size 0 / 0
VG UUID x9sUhJ-gQ4c-avxR-daQ1-ceib-VtGF-nvwqv9
9.查看系统当前lv的情况
[[email protected] ~]# lvdisplay
--- Logical volume ---
LV Path /dev/vg_rhel64/lv_root
LV Name lv_root
VG Name vg_rhel64
LV UUID Y2oXR6-yrXx-fetw-GiOl-iHmc-HbOV-fIUc83
LV Write Access read/write
LV Creation host, time rhel64.oracle.com, 2017-11-13 21:47:39 +0800
LV Status available
#open 1
LV Size 12.54 GiB
Current LE 3210
Segments 1
Allocation inherit
Read ahead sectors auto
currently set to 256
Block device 253:0
--- Logical volume ---
LV Path /dev/vg_rhel64/lv_swap
LV Name lv_swap
VG Name vg_rhel64
LV UUID OuuBWZ-WqMd-kZ5B-ka62-Ifgy-hfD5-6bpdZL
LV Write Access read/write
LV Creation host, time rhel64.oracle.com, 2017-11-13 21:47:42 +0800
LV Status available
#open 1
LV Size 1.97 GiB
Current LE 504
Segments 1
Allocation inherit
Read ahead sectors auto
currently set to 256
Block device 253:1
--- Logical volume ---
LV Path /dev/vg_myvg/lv_mylv
LV Name lv_mylv
VG Name vg_myvg
LV UUID vFq38A-3mJ1-RRso-2EcI-e9gO-wz2a-YWU3x8
LV Write Access read/write
LV Creation host, time rhel64.oracle.com, 2018-01-12 14:14:35 +0800
LV Status available
#open 1
LV Size 1.99 GiB
Current LE 510
Segments 2
Allocation inherit
Read ahead sectors auto
currently set to 256
10.给lv扩容
[[email protected] ~]# lvextend /dev/vg_rhel64/lv_root /dev/sdc1
Extending logical volume lv_root to 22.54 GiB
Logical volume lv_root successfully resized
11.查看扩容后的lv
[[email protected] ~]# lvdisplay
--- Logical volume ---
LV Path /dev/vg_rhel64/lv_root
LV Name lv_root
VG Name vg_rhel64
LV UUID Y2oXR6-yrXx-fetw-GiOl-iHmc-HbOV-fIUc83
LV Write Access read/write
LV Creation host, time rhel64.oracle.com, 2017-11-13 21:47:39 +0800
LV Status available
#open 1
LV Size 22.54 GiB
Current LE 5769
Segments 2
Allocation inherit
Read ahead sectors auto
currently set to 256
Block device 253:0
--- Logical volume ---
LV Path /dev/vg_rhel64/lv_swap
LV Name lv_swap
VG Name vg_rhel64
LV UUID OuuBWZ-WqMd-kZ5B-ka62-Ifgy-hfD5-6bpdZL
LV Write Access read/write
LV Creation host, time rhel64.oracle.com, 2017-11-13 21:47:42 +0800
LV Status available
#open 1
LV Size 1.97 GiB
Current LE 504
Segments 1
Allocation inherit
Read ahead sectors auto
currently set to 256
Block device 253:1
--- Logical volume ---
LV Path /dev/vg_myvg/lv_mylv
LV Name lv_mylv
VG Name vg_myvg
LV UUID vFq38A-3mJ1-RRso-2EcI-e9gO-wz2a-YWU3x8
LV Write Access read/write
LV Creation host, time rhel64.oracle.com, 2018-01-12 14:14:35 +0800
LV Status available
#open 1
LV Size 1.99 GiB
Current LE 510
Segments 2
Allocation inherit
Read ahead sectors auto
currently set to 256
Block device 253:2
12.查看系统当前的分区情况
[[email protected] ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg_rhel64-lv_root
13G 12G 104M 100% /
tmpfs 1.5G 72K 1.5G 1% /dev/shm
/dev/sdb1 485M 33M 427M 8% /boot
/dev/sda1 18G 172M 17G 1% /u01
/dev/sda2 7.9G 146M 7.4G 2% /software
/dev/mapper/vg_myvg-lv_mylv
2.0G 11M 1.9G 1% /lvm
没有扩容
13.对/扩容
[[email protected] ~]# resize2fs /dev/vg_rhel64/lv_root
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/vg_rhel64/lv_root is mounted on /; on-line resizing required
old desc_blocks = 1, new_desc_blocks = 2
Performing an on-line resize of /dev/vg_rhel64/lv_root to 5907456 (4k) blocks.
The filesystem on /dev/vg_rhel64/lv_root is now 5907456 blocks long.
14.查看扩容后分区的情况
[[email protected] ~]# df -Th
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/vg_rhel64-lv_root
ext4 23G 12G 9.5G 56% /
tmpfs tmpfs 1.5G 72K 1.5G 1% /dev/shm
/dev/sdb1 ext4 485M 33M 427M 8% /boot
/dev/sda1 ext4 18G 172M 17G 1% /u01
/dev/sda2 ext4 7.9G 146M 7.4G 2% /software
/dev/mapper/vg_myvg-lv_mylv
ext4 2.0G 11M 1.9G 1% /lvm
可以看到，/分区由原来的13G扩容到了23G
原文：http://blog.51cto.com/13489442/2060264
