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→User-space NFS server
== User-space NFS server ==
Advantage of user-space of NFS server is that it can be ran without any support in the kernel.
Also if it crashes - there is no crash of a system: just one process crashes, not kernel!
The disadvantage of user-space NFS server is its poductivity: noone no one can be faster then in-kernel implementation.
One well-known implementation of NFS server is "The LINUX User-Space NFS Server" by Olaf Kirch.
Some Linux distributions contain this package: Debian Sarge (nfs-user-server), OpenSuse 10.0 (nfs-server).
For other distribution distributions you can download sources (for example from Debian repository) and compile it.
There is a small trick you have to know about runing mountd and nfsd (these two daemons and portmap constitute
user-space server). You should run them with -r option:
# rpc.nfsd -r
</pre>
The reason is that these daemons check major number of device there where the directory to export resides.If major equals 0 then daemons suppose that it is NFS and don't want to reexport re-export it. Symptoms arethat client clients will always get a "permission denied" error. Simfs (the file system on what VE is located)is assosiated with so called unnamed device, which major equals 0. To prevent daemons from checkingforreexporting re-exporting - just use this -r option.
"The LINUX User-Space NFS Server" by Olaf Kirch implements NFSv2. It means that only files with sizes less
than 2GB are proceeded. If you intend to use such big files then you should use other user-space NFS serverimplementation: unfs3 (http://unfs3.sourceforge.net/). It implenets implemets v3 of NFS protocol standart.
[[Category: HOWTO]]
[[Category: Networking]]