### 新硬盘创建lv

##### 手动添加磁盘
```
echo "scsi add-single-device w x y z" > /proc/scsi/scsi
其中，w,x,y,z需要根据/proc/scsi/scsi文件中的数据替换
http://blog.chinaunix.net/uid-26557245-id-3307138.html

不关机添加磁盘
```
```
echo "- - -" > /sys/class/scsi_host/host0/scan  
echo "- - -" > /sys/class/scsi_host/host1/scan  
echo "- - -" > /sys/class/scsi_host/host2/scan  
```
```
1、查看磁盘#fdisk -l

2-1、创建分区(小于或等于2T)#fdisk /dev/sdb

2-2、创建分区(大于2T)#parted /dev/sdb 
                    >mklabel gpt
                    >unit s
                    >mkpart /dev/sdb1 2048s 100% ## 设置分区名称及大小
                    >q

3、更新内核分区表#partprobe /dev/sdb1
4、创建pv#pvcreate /dev/sdb1

5、创建vg# vgcreate vg_opt /dev/sdb1  ###vg_opt是该vg的名字

6、创建lv#lvcreate -L 5G -n lv_opt vg_opt  ###-L后面是lv大小，-n后面是lv名字
   100%VG#lvcreate -l  100%VG -n lv_opt vg_opt

7、格式化lv#mkfs.ext4 /dev/mapper/vg_opt-lv_opt

8、挂载lv#mount /dev/mapper/vg_opt-lv_opt /opt
9、写入fstab
/dev/mapper/vg_opt-lv_opt /opt                       ext4    defaults        1 1
```

##### 扩展lv (ext)
```
1、创建pv#pvcreate /dev/sda5
2、扩展vg#vgextend vg_opt /dev/sda5
3、扩展lv#lvextend –L +1G /dev/mapper/vg_opt-lv_opt
    100%VG#lvextend -l +100%FREE /dev/mapper/vg_opt-lv_opt
4、重定义lv大小#resize2fs /dev/mapper/vg_opt-lv_opt
```

##### 扩展lv (xfs)
```
1、创建pv#pvcreate /dev/sda5
2、扩展vg#vgextend vg_opt /dev/sda5
3、扩展lv#lvextend –L +1G /dev/mapper/vg_opt-lv_opt
    100%VG#lvextend -l +100%FREE /dev/mapper/vg_opt-lv_opt
4、重定义lv大小#xfs_growfs /dev/mapper/vg_opt-lv_opt
```

##### 其他
```
vg去掉特定pv # vgreduce centos /dev/sdb1
```