debian wheezy-如何挂载未使用的磁盘？

Question

I'm mostly a database guy but i have debian wheezy server with 4 hard disks. It was set up using one disk a while back, that one was all that was needed. Now, i need more space and the thing, i think, that is throwing me off is the UUID disk stuff.

anyway:

/mnt# lsblk -io KNAME,TYPE,SIZE,MODEL
KNAME TYPE   SIZE MODEL
sdb   disk 232.9G Hitachi HDP72502
sdc   disk 232.9G Hitachi HDP72502
sda   disk 232.9G Hitachi HDP72502
sda1  part 223.4G
sda2  part     1K
sda5  part   9.5G
sdd   disk 232.9G Hitachi HDP72502
sr0   rom   1024M DVD A  DS8A1P

Root is mounted to sda. sdb, c and d are unused, unformatted etc. i just need some more space, so i have created /mnt/ext_b/ and so on for b, c, d.

mount shows:

/dev/disk/by-uuid/1b1e97e4-3c04-4e50-8e06-b16752778717 on / type ext4 (rw,relatime,errors=remount-ro,user_xattr,barrier=1,data=ordered)

which is correct. i want to mount the others just for space, how do i get their UUIDs?

/mnt# blkid
/dev/sda5: UUID="f70ad0b2-a9d0-430a-829c-d2e37245fd71" TYPE="swap"
/dev/sda1: UUID="1b1e97e4-3c04-4e50-8e06-b16752778717" TYPE="ext4"

how do i get the UUIDs to put formatted filesystems on the disks?

/mnt# mkfs.ext4 /dev/sdb1
mke2fs 1.42.5 (29-Jul-2012)
Could not stat /dev/sdb1 --- No such file or directory

thanks in advance.

matt

Answer 1

It seems that those additional disks haven't been touched since they were connected to the server and don't have even partitions yet. In general, adding extra disk space in Linux can be done in the following steps:

1. Attach new disk to the server
2. Create partition table on it
3. Add one or more partitions to the disk
4. Format partition to the FS of your choice
5. Mounting this partition to the mount point of your choice
6. Make those mount persistent by adding appropriate line to the /etc/fstab

If you have multiple disks you may consider to create hardware RAID disk if you have RAID controller or software RAID, using mdadm tool . Both ways you'll get larger single disk(size would depend from the RAID level you choose) for which you'll need to go to step 2 and farther. It's worth mentioning that there is another way to get larger than single disk usable space from multiple disks called Logical Volume Manager or LVM . It's more sophisticated than MDM and allows to create FS snapshots and add extra disk space to the volume without need to create additional mountpoints.

Whatever you choose you'll need to create a partition table on a new disk/LVM volume/MDM disk. Here you need to make another choice - what type of partition table to use, MBR or GPT . Check Partitioning HOWTO for more details, but in general I'd recommend GPT for large non-bootable disks.

Same HOWTO will tell you, how create partition(s) on the selected disk. At this point you'll get devices like /dev/sdb1 , etc.

Then you can go to step 4, the one you already tried:

# mkfs.ext4 /dev/sdb1

That should succeed now and you'll be able to get UUID of a new FS with blkid . Add obtained UUID to your /etc/fstab file and mount newly created FS to it's mount point.

Answer 2

It seems to me that you must create partitions on disks. Think about storing your data. You have similar disks. It must be raid? If it must be raid, what type of raid it must be?

You can create partition with fdisk or some alternatives ( gparted , cfdisk and so on). There are a lot information in internet and manuals.

May be you need LVM? Some people say that it may slow down your database, but it gives you opportunity to get snapshots.

After creating partitions you can create filesystem and can mount it. Usually people recommend to use XFS or Ext4 for databases.

And don't forget to set right mount flags to your filestystem. noatime , nodiratime and barrier=0 will improve performance, but with barrier=0 in some cases you can loose your data. In case of Ext4 look at data (may be in your case you can set it in ordered ).

UPD: may be this question must be in superuser or unix section?

Answer 3

您应该先使用fdisk，cfdi​​sk，gparted或partitionmanager等实用程序创建分区 ，然后再对其进行格式化。