起因

VPS上mysql突然拒絕服務了，SSH上去檢查一下發現是使用者上傳大量圖片，導致磁碟空間滿了。
聯絡IDC，給增加了一塊硬碟，嗯，這下空間足夠了。

啟用新硬碟

使用 fdisk -l 檢視新增的硬碟

Disk /dev/sdb: 64.4 GB, 64424509440 bytes
255 heads, 63 sectors/track, 7832 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512
 
 bytes / 512 bytes
Disk identifier: 0x1d2d511e

使用 fdisk /dev/sdb 建立分割槽，然後格式化

mkfs.ext4 /dev/sdb1 #就分了一個區

同步資料

mount /mnt/sdb1 /dev/sdb1   #掛載分割槽
mkdir /mnt/sdb1/upload
rsync -azvP /data/wwwroot/upload/ /mnt/sdb1/upload/ #資料同步
ln -s /mnt/sdb1/upload/ /data/wwwroot/upload/ #軟連線過去

小問題

軟連線特殊處理

du -shL DIR
rsync -azvPl SRC TAR

使用中發現vsftpd不支援軟連線，改用mount

mount --bind /mnt/sdb1/upload /data/wwwroot/upload/

這樣就可以解決vsftpd的問題了

如何在不重啟的情況下檢測新硬碟

[root@localhost ~]# ll /sys/class/scsi_host/
lrwxrwxrwx  1 root root 0 2017-08-22 00:43:19 host0 -> ../../devices/pci0000:00/0000:00:10.0/host0/scsi_host/host0
lrwxrwxrwx  1 root root 0 2017-08-22 00:43:19 host1 -> ../../devices/pci0000
 
:00/0000:00:07.1/host1/scsi_host/host1
lrwxrwxrwx  1 root root 0 2017-08-22 00:43:19 host2 -> ../../devices/pci0000:00/0000:00:07.1/host2/scsi_host/host2
[root@localhost ~]# echo "- - -" > /sys/class/scsi_host/host0/scan #立即掃描scsi_host0
[root@localhost ~]# echo "- - -" > /sys/class/scsi_host/host1/scan #立即掃描scsi_host1
[root@localhost ~]# echo "- - -" > /sys/class/scsi_host/host2/scan #立即掃描scsi_host2

[root@localhost ~]# fdisk -l

Disk /dev/sda: 64.4 GB, 64424509440 bytes
255 heads, 63 sectors/track, 7832 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000078ed

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1         128     1024000   83  Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2             128        2168    16384000   82  Linux swap / Solaris
/dev/sda3            2168        7833    45505536   83  Linux

Disk /dev/sdb: 64.4 GB, 64424509440 bytes
255 heads, 63 sectors/track, 7832 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x1d2d511e

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1        7832    62910508+  83  Linux

Disk /dev/sdc: 1073.7 GB, 1073741824000 bytes
255 heads, 63 sectors/track, 130541 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x3fb96501
   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1      130541  1048569558+  83  Linux

這樣就能看到新增的第三塊硬碟了