lvextend逻辑卷扩容（xfs_growfs、resize2fs配合扩展文件系统）

lvextend 命令用于逻辑卷在线扩容&＃xff0c;也就是说lvextend扩容是不需要停机的&＃xff0c;应用服务也不需要关闭&＃xff0c;其语法格式如下&＃xff1a;

lvextend [参数] LogicalVolume[Path] [ PhysicalVolumePath… ]

常用参数&＃xff1a;
-l &＃43; &＃xff1a;指定逻辑卷的LE个数&＃xff0c;如 -l &＃43;200
-L &＃43; &＃xff1a;表示增加多少空间&＃xff0c;如 -L &＃43;15G &＃xff0c;单位有bBsSkKmMgGtTpPeE
-l &＃43;100%FREE &＃xff1a;表示增加vg的全部可用空间

PS&＃xff1a;lvextend 扩展后只是扩展了lv的大小&＃xff0c;而此时文件系统并未感知到&＃xff0c;所有还需要使用xfs_growfs、resize2fs等命令来扩展文件系统&＃xff0c;xfs_growf命令是扩展xfs文件系统&＃xff0c;resize2fs是扩展ext4文件系统。

演示示例&＃xff1a;

方法一、
[root&＃64;localhost lv_data]# lvextend -L &＃43;1G /dev/iflytek/lv_data #逻辑卷扩容&＃xff0c;增加1个G的空间Size of logical volume iflytek/lv_data changed from 6.00 GiB (1536 extents) to 7.00 GiB (1792 extents).Logical volume iflytek/lv_data successfully resized.
[root&＃64;localhost mapper]# lvsLV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convertroot cl -wi-ao---- 9.79g swap cl -wi-ao---- 1.20g lv_data iflytek -wi-ao---- 7.00g #发现lv_data其实增大到7G了
[root&＃64;localhost lv_data]# df -Th #发现/dev/mapper/iflytek-lv_data逻辑卷还是6G&＃xff0c;这说明即使lv增大了但文件系统并未感知到lv增大了
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/cl-root xfs 9.8G 1021M 8.8G 11% /
devtmpfs devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs tmpfs 1.9G 8.6M 1.9G 1% /run
tmpfs tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 139M 876M 14% /boot
tmpfs tmpfs 378M 0 378M 0% /run/user/0
/dev/mapper/iflytek-lv_data xfs 6.0G 33M 6.0G 1% /lv_data
[root&＃64;localhost lv_data]#
#哎呀&＃xff0c;df -Th 看到的怎么是/dev/mapper/iflytek-lv_data&＃xff0c;我们的逻辑卷文件明明是/dev/iflytek/lv_data的呀&＃xff0c;怎么回事&＃xff1f;
#原来这是lvm的mapper机制决定的&＃xff0c;当我们lvcreate一个逻辑卷的时候&＃xff0c;Linux会新建两个软链接文件&＃xff0c;如/dev/PVName/PVName和/dev/mapper/PVName-LVName,而这2个文件都是指向/dev/dm-X 块文件的&＃xff0c;所有&＃xff0c;当我们使用df -h看到的/dev/mapper/iflytek-lv_data其实是和/dev/iflytek/lv_data一样的&＃xff0c;不管我们使用哪个都是可以的。如果使用xfs文件系统xfs_growfs /dev/iflytek/lv_data
如果使用ext4文件系统resize2fs /dev/root_vg/root[root&＃64;localhost mapper]# xfs_growfs /dev/iflytek/lv_data #使用xfs_growfs命令扩展xfs文件系统,如果是ext4文件系统&＃xff0c;则使用resize2fs /dev/iflytek/lv_data
meta-data&＃61;/dev/mapper/iflytek-lv_data isize&＃61;512 agcount&＃61;4, agsize&＃61;393216 blks&＃61; sectsz&＃61;512 attr&＃61;2, projid32bit&＃61;1&＃61; crc&＃61;1 finobt&＃61;0 spinodes&＃61;0
data &＃61; bsize&＃61;4096 blocks&＃61;1572864, imaxpct&＃61;25&＃61; sunit&＃61;0 swidth&＃61;0 blks
naming &＃61;version 2 bsize&＃61;4096 ascii-ci&＃61;0 ftype&＃61;1
log &＃61;internal bsize&＃61;4096 blocks&＃61;2560, version&＃61;2&＃61; sectsz&＃61;512 sunit&＃61;0 blks, lazy-count&＃61;1
realtime &＃61;none extsz&＃61;4096 blocks&＃61;0, rtextents&＃61;0
data blocks changed from 1572864 to 1835008
[root&＃64;localhost mapper]# df -Th #检查
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/cl-root xfs 9.8G 1021M 8.8G 11% /
devtmpfs devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs tmpfs 1.9G 8.6M 1.9G 1% /run
tmpfs tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 139M 876M 14% /boot
tmpfs tmpfs 378M 0 378M 0% /run/user/0
/dev/mapper/iflytek-lv_data xfs 7.0G 33M 7.0G 1% /lv_data #大小其实增大了1G了
[root&＃64;localhost mapper]#


方法二、
[root&＃64;localhost mapper]# lvextend -l &＃43;25 /dev/iflytek/lv_data #增加25个LE就是100MSize of logical volume iflytek/lv_data changed from 7.00 GiB (1792 extents) to 7.10 GiB (1817 extents).Logical volume iflytek/lv_data successfully resized.
[root&＃64;localhost mapper]# df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/mapper/cl-root 10258432 1045568 9212864 11% /
devtmpfs 1921808 0 1921808 0% /dev
tmpfs 1932776 0 1932776 0% /dev/shm
tmpfs 1932776 8776 1924000 1% /run
tmpfs 1932776 0 1932776 0% /sys/fs/cgroup
/dev/sda1 1038336 141608 896728 14% /boot
tmpfs 386556 0 386556 0% /run/user/0
/dev/mapper/iflytek-lv_data 7329792 32980 7296812 1% /lv_data #查看容量大小
[root&＃64;localhost mapper]# xfs_growfs /dev/iflytek/lv_data #扩展文件系统大小
meta-data&＃61;/dev/mapper/iflytek-lv_data isize&＃61;512 agcount&＃61;5, agsize&＃61;393216 blks&＃61; sectsz&＃61;512 attr&＃61;2, projid32bit&＃61;1&＃61; crc&＃61;1 finobt&＃61;0 spinodes&＃61;0
data &＃61; bsize&＃61;4096 blocks&＃61;1835008, imaxpct&＃61;25&＃61; sunit&＃61;0 swidth&＃61;0 blks
naming &＃61;version 2 bsize&＃61;4096 ascii-ci&＃61;0 ftype&＃61;1
log &＃61;internal bsize&＃61;4096 blocks&＃61;2560, version&＃61;2&＃61; sectsz&＃61;512 sunit&＃61;0 blks, lazy-count&＃61;1
realtime &＃61;none extsz&＃61;4096 blocks&＃61;0, rtextents&＃61;0
data blocks changed from 1835008 to 1860608 #显示块已经增大了
[root&＃64;localhost mapper]# df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/mapper/cl-root 10258432 1045568 9212864 11% /
devtmpfs 1921808 0 1921808 0% /dev
tmpfs 1932776 0 1932776 0% /dev/shm
tmpfs 1932776 8776 1924000 1% /run
tmpfs 1932776 0 1932776 0% /sys/fs/cgroup
/dev/sda1 1038336 141608 896728 14% /boot
tmpfs 386556 0 386556 0% /run/user/0
/dev/mapper/iflytek-lv_data 7432192 32980 7399212 1% /lv_data #空间增大了
[root&＃64;localhost mapper]#


方法三、
[root&＃64;localhost mapper]# lvs #查看还有多少空间LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convertroot cl -wi-ao---- 9.79g swap cl -wi-ao---- 1.20g lv_data iflytek -wi-ao---- 7.10g #还有7.10G
[root&＃64;localhost mapper]# lvextend -l &＃43;100%FREE /dev/iflytek/lv_data #把vg的全部剩余空间都加给lvSize of logical volume iflytek/lv_data changed from 7.10 GiB (1817 extents) to 13.99 GiB (3582 extents).Logical volume iflytek/lv_data successfully resized.
[root&＃64;localhost mapper]# lvs #lv确实增加了LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convertroot cl -wi-ao---- 9.79g swap cl -wi-ao---- 1.20g lv_data iflytek -wi-ao---- 13.99g
[root&＃64;localhost mapper]# vgs #iflytek卷组显示已经没有剩余空间了 VG #PV #LV #SN Attr VSize VFreecl 1 2 0 wz--n- 11.00g 4.00miflytek 2 1 0 wz--n- 13.99g 0
[root&＃64;localhost mapper]# df -Th #此时文件系统还没扩展
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/cl-root xfs 9.8G 1021M 8.8G 11% /
devtmpfs devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs tmpfs 1.9G 8.6M 1.9G 1% /run
tmpfs tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 139M 876M 14% /boot
tmpfs tmpfs 378M 0 378M 0% /run/user/0
/dev/mapper/iflytek-lv_data xfs 7.1G 33M 7.1G 1% /lv_data
[root&＃64;localhost mapper]# xfs_growfs /dev/iflytek/lv_data #扩展文件系统大小
meta-data&＃61;/dev/mapper/iflytek-lv_data isize&＃61;512 agcount&＃61;5, agsize&＃61;393216 blks&＃61; sectsz&＃61;512 attr&＃61;2, projid32bit&＃61;1&＃61; crc&＃61;1 finobt&＃61;0 spinodes&＃61;0
data &＃61; bsize&＃61;4096 blocks&＃61;1860608, imaxpct&＃61;25&＃61; sunit&＃61;0 swidth&＃61;0 blks
naming &＃61;version 2 bsize&＃61;4096 ascii-ci&＃61;0 ftype&＃61;1
log &＃61;internal bsize&＃61;4096 blocks&＃61;2560, version&＃61;2&＃61; sectsz&＃61;512 sunit&＃61;0 blks, lazy-count&＃61;1
realtime &＃61;none extsz&＃61;4096 blocks&＃61;0, rtextents&＃61;0
data blocks changed from 1860608 to 3667968
[root&＃64;localhost mapper]# df -Th #文件系统已扩展
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/cl-root xfs 9.8G 1021M 8.8G 11% /
devtmpfs devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs tmpfs 1.9G 8.6M 1.9G 1% /run
tmpfs tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 139M 876M 14% /boot
tmpfs tmpfs 378M 0 378M 0% /run/user/0
/dev/mapper/iflytek-lv_data xfs 14G 33M 14G 1% /lv_data
[root&＃64;localhost mapper]#