NBD Network block Device usage tutorial

http://blog.csdn.net/gui694278452/article/details/7652450

I. NBD profile NBD (Network block Device) allows you to use the disk space of a remote host as a piece of equipment. It's like a hard drive.
With it, you can easily add another server's hard disk space to the local server.
NBD is different from NFS. NFS simply provides a mount point for clients to use, and the client cannot change the partition format of the mount point.
The NBD provides a block device that the client can format into various types of partitions. More user-friendly.
NBD is a kernel module that most Linux distributions already contain.
Two. NBD Installation method
In more than 10 versions of Turbolinux, NBD has been compiled into modules. Saved in
The/lib/modules/$version/kernel/driver/block/.
You also need to install Nbd-server and nbd-client Tools on both the server side and the client.
You can download source packages from the official website and install them on both the server and client servers:
Http://sourceforge.net/projects/nbd
We download nbd-2.8.8.tar.bz2 here
After downloading, perform the following steps to install:
# tar jxf nbd-2.8.8.tar.bz2
# CD nbd-2.8.8
#./configure
# make

# make Install

or install using the command line:

sudo apt-get install nbd-client

sudo apt-get install nbd-server three. NBD Use method
1. Example 1: Server-side provides a single image file to the client
A. Server-side configuration method (IP 192.168.1.1)
You need to create a disk image file to use as a block device for the client. We make a 300MB file as a block device.
# cd/var/tmp
# dd If=/dev/zero of=nbd-disk0 bs=104857600 count=3
Start Nbd-server, listen for port 1234, use Nbd-disk0 image file.
# Nbd-server 1234/var/tmp/nbd-disk0
View the NBD process.
# Ps-ef | grep NBD
Root 11292 1 0 15:02? 00:00:00 Nbd-server 1234/var/tmp/nbd-disk0
Nbd-server usage:
Nbd-server port file [SIZE][KKMM] [-l authorize_file] [-R] [-m] [-c] [-a timeout_sec]
Port Nbd-server listening ports.
The image file of the file binding.
Size of the block device that is seen by the client (in the unit can be: k,k,m,m).
-r|--read-only read-only mode, the client cannot write on a block device.
-m|--multi-file multiple files, you can provide multiple image files as a block device to the client.
-c|--copy-on-write all client writes will be saved as a file, and the file will be deleted after the connection is disconnected.
You can guarantee that the image file content will not be modified.
-l|--authorize-file file a list of hosts that allow access to this NBD.
-a|--idle-time server disconnects the maximum idle time before connecting to the client.
B. Client configuration method (IP is 192.168.1.2)
Load the NBD module.
# modprobe NBD
# Lsmod | grep NBD
NBD 26400 0
Check to see if the NBD device is established.
# ls/dev/nbd*-HL
Brw-r-----1 root disk, 0 June 06:40/dev/nbd0
Brw-r-----1 root disk, 1 June 06:40/DEV/NBD1
Brw-r-----1 root disk, 2 June 06:40/dev/nbd2
Brw-r-----1 root disk, 3 June 06:40/dev/nbd3
Brw-r-----1 root disk, 4 June 06:40/dev/nbd4
Brw-r-----1 root disk, 5 June 06:40/dev/nbd5
Brw-r-----1 Root disk, 6 June 06:40/dev/nbd6
Brw-r-----1 Root disk, 7 June 06:40/dev/nbd7
Brw-r-----1 root disk, 8 June 06:40/dev/nbd8
Brw-r-----1 Root disk, 9 June 06:40/DEV/NBD9
Connect the/DEV/NBD0 device to the host.
# nbd-client 192.168.1.1 1234/dev/nbd0
Negotiation:.. Size = 307200KB
bs=1024, sz=307200
Nbd-client usage:
Nbd-client [Bs=blocksize] host Port Nbd_device [-swap]
BS is used to set block size, default is 1024, can be 512,1024.2048,4096
Hostname or IP of host server
Listening port for Port server
Nbd_device map to which of the local NBD devices (such as:/DEV/NBD0)
-SWAP Specifies that the NBD device will be used as swap space
Nbd-client-d Nbd_device for disconnecting
Once the connection is successful, you can view the nbd-client process.
# Ps-ef | grep NBD
Root 3156 1 0 06:44 pts/0 00:00:00 nbd-client 192.168.1.1 1234/dev/nbd0
Before using, you need to format this piece of equipment.
# mkfs.ext3/dev/nbd0
MKE2FS 1.39 (29-may-2006)
FileSystem label=
OS Type:linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
76912 inodes, 307200 blocks
15360 blocks (5.00%) reserved for the Super user
The Data block=1
Maximum filesystem blocks=67633152
Block groups
8192 blocks per group, 8192 fragments per group
2024 Inodes per group
Superblock backups stored on blocks:
8193, 24577, 40961, 57345, 73729, 204801, 221185
Writing Inode Tables:done
Creating journal (8192 blocks): Done
Writing superblocks and filesystem accounting Information:done
This filesystem would be automatically checked every mounts or
180 days, whichever comes. Use Tune2fs-c or-i to override.
Mount this block device.
# mkdir/mnt/nbd0
# mount/dev/nbd0/mnt/nbd0
# cd/mnt/nbd0
# ls
Lost+found
Copy the/root directory into this directory.
# Cp/root. -rf
# ls
Lost+found Root
Disconnect the block device.
# umount/mnt/nbd0/
# nbd-client-d/dev/nbd0
Disconnecting:que, disconnect, sock, done
Kernel call Returned:broken Pipeclosing:que, sock, done
2. Example 2: Server-side provides multiple image files to client
A. Server-side configuration
# cd/var/tmp
# dd If=/dev/zero of=nbd-disk1 bs=104857600 count=3
Recorded the 3+0 reading.
Record the writing of 3+0.
314572800 bytes (315 MB) replicated, 0.584027 seconds, 539 mb/sec
# dd If=/dev/zero of=nbd-disk2 bs=104857600 count=3
Recorded the 3+0 reading.
Record the writing of 3+0.
314572800 bytes (315 MB) replicated, 1.5128 seconds, in the same MB/sec
# Nbd-server 1234/var/tmp/nbd-disk1
# Nbd-server 1235/var/tmp/nbd-disk1
# Nbd-server 1236/var/tmp/nbd-disk2
# Ps-ef | grep NBD
Root 11292 1 0 15:02? 00:00:00 Nbd-server 1234/var/tmp/nbd-disk0
Root 11599 1 0 15:14? 00:00:00 Nbd-server 1235/var/tmp/nbd-disk1
Root 11606 1 0 15:14? 00:00:00 Nbd-server 1236/var/tmp/nbd-disk2
B. Client Configuration
# Lsmod | grep NBD
NBD 24736 0
# ls/dev/nbd*
/dev/nbd0/dev/nbd11/dev/nbd14/dev/nbd3/dev/nbd6/dev/nbd9
/dev/nbd1/dev/nbd12/dev/nbd15/dev/nbd4/dev/nbd7
/dev/nbd10/dev/nbd13/dev/nbd2/dev/nbd5/dev/nbd8
# nbd-client 192.168.1.1 1234/dev/nbd0
Negotiation:.. Size = 307200KB
bs=1024, sz=307200
# nbd-client 192.168.1.1 1235/DEV/NBD1
Negotiation:.. Size = 307200KB
bs=1024, sz=307200
# nbd-client 192.168.1.1 1236/dev/nbd2
Negotiation:.. Size = 307200KB
bs=1024, sz=307200
Format NBD1 into VFAT format.
# MKFS.VFAT/DEV/NBD1
Mkfs.vfat 2.11 (Mar 2005)
Unable to get drive geometry, using default 255/63
Format nbd2 into ext2 format.
# MKFS.EXT2/DEV/NBD2
MKE2FS 1.39 (29-may-2006)
FileSystem label=
OS Type:linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
76912 inodes, 307200 blocks
15360 blocks (5.00%) reserved for the Super user
The Data block=1
Maximum filesystem blocks=67633152
Block groups
8192 blocks per group, 8192 fragments per group
2024 Inodes per group
Superblock backups stored on blocks:
8193, 24577, 40961, 57345, 73729, 204801, 221185
Writing Inode Tables:done
Writing superblocks and filesystem accounting Information:done
This filesystem would be automatically checked every mounts or
180 days, whichever comes. Use Tune2fs-c or-i to override.
Mount these 3 block devices
# cd/mnt
# mkdir NBD1 Nbd2
# mount/dev/nbd0 Nbd0
# MOUNT/DEV/NBD1 NBD1
# mount/dev/nbd2 Nbd2
# df-h
FileSystem Size Used Avail use% mounted on
/dev/nbd0 291M 11M 265M 4%/mnt/nbd0
/DEV/NBD1 300M 0 300M 0%/mnt/nbd1
/dev/nbd2 291M 2.1M 274M 1%/mnt/nbd2
# mount
/dev/nbd0 on/mnt/nbd0 type ext3 (rw)
/DEV/NBD1 on/mnt/nbd1 type VFAT (rw)
/dev/nbd2 on/mnt/nbd2 type ext2 (rw)