一、名詞解釋
1、什么是NFS？
全稱 network file system網(wǎng)絡(luò)文件系統(tǒng)
通過網(wǎng)絡(luò)存儲和組織文件的一種方法或機制2、什么是文件系統(tǒng)
文件系統(tǒng)是操作系統(tǒng)用于明確存儲設(shè)備（常見的是磁盤，也有基于NAND Flash的固態(tài)硬盤）或分區(qū)上的文件的方法和數(shù)據(jù)結(jié)構(gòu)；即在存儲設(shè)備上組織文件的方法。操作系統(tǒng)中負責管理和存儲文件信息的軟件機構(gòu)稱為文件管理系統(tǒng)，簡稱文件系統(tǒng)。文件系統(tǒng)由三部分組成：文件系統(tǒng)的接口，對對象操縱和管理的軟件集合，對象及屬性。從系統(tǒng)角度來看，文件系統(tǒng)是對文件存儲設(shè)備的空間進行組織和分配，負責文件存儲并對存入的文件進行保護和檢索的系統(tǒng)。具體地說，它負責為用戶建立文件，存入、讀出、修改、轉(zhuǎn)儲文件，控制文件的存取，當用戶不再使用時撤銷文件等。
3、為什么要用共享存儲
前端所有的應(yīng)用服務(wù)器接受到用戶上的圖片、文件、視頻，都會統(tǒng)一的放到后端的存儲上。
為什么要共享存儲？所有節(jié)點服務(wù)器都需要將內(nèi)容存到存儲上，取的統(tǒng)一來取
4、共享存儲的種類
單點存儲系統(tǒng)就是NFS，中小型企業(yè)，阿里云服務(wù)器的NAS服務(wù)。OSS對象存儲
大型企業(yè)用FastDFS、Ceph、GlsterFS、Mfs
硬件存儲：傳統(tǒng)企業(yè)：穩(wěn)定、2臺 雙主機頭 幾十塊硬盤 RAID10
二、原理及實現(xiàn)
1、NFS工作原理
NFS網(wǎng)絡(luò)文件系統(tǒng)
啟動NFS服務(wù)，而且還要啟動很多端口
NFS功能，需要很多服務(wù)。每個服務(wù)都有端口，而且經(jīng)常變化
如何要讓客戶端找到這些端口呢？就需要一個rpc服務(wù)
NFS服務(wù)：
1、NFS服務(wù)（有很多進程和端口）? ?port:2049
2、RPC服務(wù)（對外固定端口111）
客戶端請求NFS服務(wù)，先找RPC 111端口，找到NFS的端口。
配置文件? /etc/exports
[root@backup backup]# man exports
EXAMPLE
? ? ? # sample /etc/exports file
? ? ? /? ? ? ? ? ? ? master(rw) trusty(rw,no_root_squash)
? ? ? /projects? ? ? proj*.local.domain(rw)
? ? ? /usr? ? ? ? ? ? *.local.domain(ro) @trusted(rw)
? ? ? /home/joe? ? ? pc001(rw,all_squash,anonuid=150,anongid=100)
? ? ? /pub? ? ? ? ? ? *(ro,insecure,all_squash)
? ? ? /srv/www? ? ? ? -sync,rw server @trusted @external(ro)
? ? ? /foo? ? ? ? ? ? 2001:db8:9:e54::/64(rw) 192.0.2.0/24(rw)
? ? ? /build? ? ? ? ? buildhost[0-9].local.domain(rw)
? ? ? The? first? line exports the entire filesystem to machines master and trusty.? In addition to write access, all uid squashing is turned off for host trusty.
? ? ? The second and third entry show examples for wildcard hostnames and netgroups (this is the entry `@trusted'). The fourth line shows the entry for the PC/NFS
? ? ? client? discussed? above.? Line 5 exports the public FTP directory to every host in the world, executing all requests under the nobody account. The insecure
? ? ? option in this entry also allows clients with NFS implementations that don't use a reserved port for NFS.? The sixth line exports a directory read-write? to
? ? ? the machine 'server' as well as the `@trusted' netgroup, and read-only to netgroup `@external', all three mounts with the `sync' option enabled. The seventh
? ? ? line exports a directory to both an IPv6 and an IPv4 subnet. The eighth line demonstrates a character class wildcard match.
FILES
? ? ? /etc/exports /etc/exports.d
1）待共享的目錄 存東西的目錄 取東西的目錄 例如：/date
2）訪問的主機
? ? 172.16.1.7 （web1） 單個主機
? ? 172.16.1.0/24? ? ? ? ?網(wǎng)段
? ? 172.16.1.*? ? ? ? ? ? ? 網(wǎng)段
3）（）權(quán)限
? ? ? rw? ? ? 可讀? ?read? ?write? ?安全? ?慢?
? ? ?async? 異步寫到遠端緩沖區(qū) 不安全? 快??
實踐：
服務(wù)器端：
0、安裝rpcbind和nfs-utils.x86_64 并啟動服務(wù)
yum install -y nfs-utils.x86_64? rpcbind?
systemctl start nfs-utils.service?
systemctl enable nfs-utils.service?
systemctl start? rpcbind
systemctl enable rpcbind
檢查端口注冊
rpcinfo -p 127.0.0.1
1、修改exports文件
[root@nfs01 172.16.1.31]# cat /etc/exports
#wushuo shared dir at time
/date 172.16.1.0/24(rw,sync)
2、創(chuàng)建文件
[root@nfs01 172.16.1.31]# mkdir -p /data
[root@nfs01 172.16.1.31]# ll -d /data
drwxr-xr-x 2 root root 6 Apr 17 11:53 /data
修改文件所屬主組
[root@nfs01 172.16.1.31]# ll -d /data/
drwxr-xr-x 2 nfsnobody nfsnobody 6 Apr 17 11:53 /data/
3、重啟并檢查檢查服務(wù)
[root@nfs01 172.16.1.31]# exportfs -r或
[root@nfs01 172.16.1.31]# systemctl reload nfs.service?
[root@nfs01 172.16.1.31]# systemctl status nfs.service?
● nfs-server.service - NFS server and services
? ?Loaded: loaded (/usr/lib/systemd/system/nfs-server.service; enabled; vendor preset: disabled)
? ?Active: active (exited) since Wed 2019-04-17 11:56:12 CST; 1min 2s ago
? Process: 9740 ExecStopPost=/usr/sbin/exportfs -f (code=exited, status=0/SUCCESS)
? Process: 9736 ExecStopPost=/usr/sbin/exportfs -au (code=exited, status=0/SUCCESS)
? Process: 9735 ExecStop=/usr/sbin/rpc.nfsd 0 (code=exited, status=0/SUCCESS)
? Process: 9834 ExecReload=/usr/sbin/exportfs -r (code=exited, status=0/SUCCESS)
? Process: 9766 ExecStartPost=/bin/sh -c if systemctl -q is-active gssproxy; then systemctl restart gssproxy ; fi (code=exited, status=0/SUCCESS)
? Process: 9750 ExecStart=/usr/sbin/rpc.nfsd $RPCNFSDARGS (code=exited, status=0/SUCCESS)
? Process: 9748 ExecStartPre=/usr/sbin/exportfs -r (code=exited, status=1/FAILURE)
?Main PID: 9750 (code=exited, status=0/SUCCESS)
Apr 17 11:56:12 nfs01 systemd[1]: Starting NFS server and services...
Apr 17 11:56:12 nfs01 exportfs[9748]: exportfs: Failed to stat /date: No such file or directory
Apr 17 11:56:12 nfs01 systemd[1]: Started NFS server and services.
Apr 17 11:56:22 nfs01 systemd[1]: Reloading NFS server and services.
Apr 17 11:56:22 nfs01 exportfs[9789]: exportfs: Failed to stat /date: No such file or directory
Apr 17 11:56:22 nfs01 systemd[1]: Reloaded NFS server and services.
Apr 17 11:57:12 nfs01 systemd[1]: Reloading NFS server and services.
Apr 17 11:57:12 nfs01 systemd[1]: Reloaded NFS server and services.
4、檢查并掛載
[root@nfs01 172.16.1.31]# showmount -e 172.16.1.31
Export list for 172.16.1.31:
/data 172.16.1.0/24
[root@nfs01 172.16.1.31]# mount -t nfs 172.16.1.31:/data /mnt
[root@nfs01 172.16.1.31]# touch /mnt/oldboy.test123
客戶端：
0、安裝rpcbind和nfs-utils.x86_64?
yum install -y nfs-utils.x86_64? rpcbind?
systemctl start nfs-utils.service?
systemctl enable nfs-utils.service?
systemctl start? rpcbind
systemctl enable rpcbind
檢查端口注冊
rpcinfo -p 127.0.0.1
1、啟動并檢查檢查服務(wù)
[root@web01 172.16.1.31]# exportfs -r或
[root@web01 172.16.1.31]# systemctl reload nfs.service?
[root@web01 172.16.1.31]# systemctl status nfs.service?
● nfs-server.service - NFS server and services
? ?Loaded: loaded (/usr/lib/systemd/system/nfs-server.service; enabled; vendor preset: disabled)
? ?Active: active (exited) since Wed 2019-04-17 11:56:12 CST; 1min 2s ago
? Process: 9740 ExecStopPost=/usr/sbin/exportfs -f (code=exited, status=0/SUCCESS)
? Process: 9736 ExecStopPost=/usr/sbin/exportfs -au (code=exited, status=0/SUCCESS)
? Process: 9735 ExecStop=/usr/sbin/rpc.nfsd 0 (code=exited, status=0/SUCCESS)
? Process: 9834 ExecReload=/usr/sbin/exportfs -r (code=exited, status=0/SUCCESS)
? Process: 9766 ExecStartPost=/bin/sh -c if systemctl -q is-active gssproxy; then systemctl restart gssproxy ; fi (code=exited, status=0/SUCCESS)
? Process: 9750 ExecStart=/usr/sbin/rpc.nfsd $RPCNFSDARGS (code=exited, status=0/SUCCESS)
? Process: 9748 ExecStartPre=/usr/sbin/exportfs -r (code=exited, status=1/FAILURE)
?Main PID: 9750 (code=exited, status=0/SUCCESS)
Apr 17 11:56:12 nfs01 systemd[1]: Starting NFS server and services...
Apr 17 11:56:12 nfs01 exportfs[9748]: exportfs: Failed to stat /date: No such file or directory
Apr 17 11:56:12 nfs01 systemd[1]: Started NFS server and services.
Apr 17 11:56:22 nfs01 systemd[1]: Reloading NFS server and services.
Apr 17 11:56:22 nfs01 exportfs[9789]: exportfs: Failed to stat /date: No such file or directory
Apr 17 11:56:22 nfs01 systemd[1]: Reloaded NFS server and services.
Apr 17 11:57:12 nfs01 systemd[1]: Reloading NFS server and services.
Apr 17 11:57:12 nfs01 systemd[1]: Reloaded NFS server and services.
2、檢查并掛載
[root@web01 172.16.1.31]# showmount -e 172.16.1.31
Export list for 172.16.1.31:
/data 172.16.1.0/24
[root@web01 172.16.1.31]# mount -t nfs 172.16.1.31:/data /mnt
[root@web01 172.16.1.31]# touch /mnt/oldboy.test123
[root@web01 ~]# df
Filesystem? ? ? ? 1K-blocks? ? Used Available Use% Mounted on
/dev/sda3? ? ? ? ? 19911680 2575988? 17335692? 13% /
devtmpfs? ? ? ? ? ? ?229008? ? ? ?0? ? 229008? ?0% /dev
tmpfs? ? ? ? ? ? ? ? 239908? ? ? ?0? ? 239908? ?0% /dev/shm
tmpfs? ? ? ? ? ? ? ? 239908? ? 5664? ? 234244? ?3% /run
tmpfs? ? ? ? ? ? ? ? 239908? ? ? ?0? ? 239908? ?0% /sys/fs/cgroup
/dev/sda1? ? ? ? ? ? 258724? 120952? ? 137772? 47% /boot
tmpfs? ? ? ? ? ? ? ? ?47984? ? ? ?0? ? ?47984? ?0% /run/user/0
172.16.1.31:/data? 19911680 2602688? 17308992? 14% /mnt
