xref: /linux/Documentation/admin-guide/blockdev/nbd.rst (revision 17cfcb68af3bc7d5e8ae08779b1853310a2949f3)
1==================================
2Network Block Device (TCP version)
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4
51) Overview
6-----------
7
8What is it: With this compiled in the kernel (or as a module), Linux
9can use a remote server as one of its block devices. So every time
10the client computer wants to read, e.g., /dev/nb0, it sends a
11request over TCP to the server, which will reply with the data read.
12This can be used for stations with low disk space (or even diskless)
13to borrow disk space from another computer.
14Unlike NFS, it is possible to put any filesystem on it, etc.
15
16For more information, or to download the nbd-client and nbd-server
17tools, go to http://nbd.sf.net/.
18
19The nbd kernel module need only be installed on the client
20system, as the nbd-server is completely in userspace. In fact,
21the nbd-server has been successfully ported to other operating
22systems, including Windows.
23
24A) NBD parameters
25-----------------
26
27max_part
28	Number of partitions per device (default: 0).
29
30nbds_max
31	Number of block devices that should be initialized (default: 16).
32