Network file system service (NFS)

One 、NFS The basic principle

Network file system is to make Different computers Can pass between The Internet Conduct File sharing A network protocol , be chiefly used in UNIX In the network of the system .NFS The service is only used for (Linux System ) Between File sharing .

Two 、NFS working principle

NFS Service is based on The client / The server Mode .NFS Server is Provide output file （ Shared directory file ） The computer , and NFS The client is Access the output file The computer , It can mount the output file to a directory file in its own system .

NFS The customer and NFS Server pass Remote procedure call protocol Realization The data transfer .NFS If the directory on the server can be accessed by remote users , It's called export （export）; The process of the client host accessing the server export directory is called mount （mount） Or import .

3、 ... and 、NFS Components

NFS Services are mainly provided by 6 Component composition . front 3 Required , after 3 Options .
1、rpc.nfsd : Judge 、 Check whether the client has the permission to log in to the host , Responsible for handling NFS request
2、rpc.mounted ： management NFS File system
3、rpcbind ： Conduct Port mapping Work
4、rpc.locked： Handle lock recovery of crashed systems
5、rpc.stated： Handle the file locking problem between the client and the server
6、rpc.quotad： Provide NFS Interface with quota management program .

Four 、 install 、 Start and stop NFS The server

1、 The kit you need

At least two kits are required
（1）rpcbind
（2）nfs-utils
nfs-utils Provide rpc.nfsd and rpc.mounted These two daemons and other related documents 、 Suite of execution files .

2、 install NFS service

Check whether the system is installed NFS Dependency packages
rpm -qa|grep nfs-utils
rpm -qa|grep rpcbind
（1） Use yum Command to install NFS service
yum clean all // Clear the cache before installing
yum install rpcbind -y
yum install nfs-utils -y
（2） Use rpm Command to query again
rpm -qa|grep nfs
Query results ：
libnfsidmap…
nfs-utils…
rpm -qa|grep rpc
Query results ：
libtirpc…
xmlrpc…
rpcbind…
xmlrpc-c-client…

3、 start-up NFS service

Inquire about NFS Whether the program of is running normally
rpcinfo -p
If you don't see nfs and mounted Options , shows NFS Not running , Need to start it . Start with the following command .
systemctl start rpcbind
systemctl start nfs
systemctl start nfs-server
systemctl enable nfs-server
systemctl enable rpcbind

5、 ... and 、 To configure NFS service

Primary profile ：/etc/exports

1、 Virtual machine required

a NFS The server , The host name is Server1, Plan well IP Address: e.g ：192.168.10.1
a NFS client , The host name is Client1, Plan well IP Address: e.g ：192.168.10.20
NFS The network connection mode of server and client is VMnet1

2、exports File format

If there is no /etc/exports, Then create it manually .
mkdir /tmp1
vim /etc/exports
/tmp1 192.168.10.20/24(ro) localhost(rw) *(ro,sync)
# share directory The first mainframe （ jurisdiction ） Available host names Other hosts （ Wildcards available ）