NFS(5) File Formats Manual NFS(5) nfs - fstab nfs /etc/fstab NFS 1984. NFS . Linux NFS NFS 3 4.0 4.1 4.2. mount(8) . /etc/fstab mount(8) ( NFS). /etc/fstab . NFS /etc/fstab NFS . NFS . : server:path /mountpoint fstype option,option,... 0 0 . . IPv4 IPv6 . IPv6 (Link-local) (Site-local) . ipv6(7) IPv6 . fstype "nfs". "nfs4" /etc/fstab . mount(8) . defaults /etc/fstab. NFS. nfsvers=n NFS NFS . . 4.2 . vers=n nfsvers. soft / softerr / hard NFS NFS. ( hard) NFS . soft softerr NFS NFS retrans NFS EIO ( soft) ETIMEDOUT ( softerr) . : "" (soft) . soft softerr . NFS TCP retrans soft softerr. softreval / nosoftreval NFS NFS retrans . . softreval soft retrans. hard . : nosoftreval hard soft. intr / nointr . 2.6.25. timeo=n ( ) NFS NFS. NFS TCP timeo 600 (60 ). NFS : timeo 600 . NFS UDP ( READ WRITE) timeo ( FSINFO). timeo 1.1 . NFS 60 . timeo . TCP RDMA 600 (60 ). UDP 60 (6 ). retrans=n NFS . retrans NFS UDP TCP . NFS " " retrans ( hard ). rsize=n READ NFS NFS. NFS READ rsize . Linux NFS 1,048,576 ( ). rsize . rsize 1024 4096 1048576 1048576. . rsize rsize rsize . rsize mount(8) /etc/mtab. rsize /proc/mounts. wsize=n WRITE NFS NFS. NFS WRITE wsize . Linux NFS 1,048,576 ( ). rsize wsize . wsize 1024 4096 1048576 1048576. . wsize wsize wsize . wsize mount(8) /etc/mtab. wsize /proc/mounts. ac / noac . ( ac) . NFS . NFS . . noac . noac . . noac NFS . . DATA AND METADATA COHERENCE . acregmin=n () NFS . NFS 3 . DATA AND METADATA COHERENCE . acregmax=n () NFS . NFS 60 . DATA AND METADATA COHERENCE . acdirmin=n () NFS . NFS 30 . DATA AND METADATA COHERENCE . acdirmax=n () NFS . NFS 60 . DATA AND METADATA COHERENCE . actimeo=n actimeo acregmin acregmax acdirmin acdirmax . NFS . bg / fg mount(8) . fg mount(8) . " " fg bg. bg mount(8) . . "". mount(8) . NFS /etc/fstab NFS . ( automount(8) ). nconnect=n TCP . / (NICs) . nconnect 16. nconnect pNFS . rdirplus / nordirplus NFS v3 v4 READDIRPLUS. NFS READDIR READDIRPLUS READDIRPLUS. READDIR . rdirplus={none|force} "force" NFS READDIRPLUS. "none" nordirplus. retry=n mount(8) NFS . 10000 ( 80 ). mount(8) . . UDP timeo retrans 7 . TCP 3 TCP . sec=flavors . . sec= . (flavors) none sys krb5 krb5i krb5p. SECURITY CONSIDERATIONS . sharecache / nosharecache . . sharecache . nosharecache . . 2.6.18 nosharecache (). . resvport / noresvport NFS NFS . resvport NFS . noresvport NFS . 2.6.28 . NFS NFS . SECURITY CONSIDERATIONS . lookupcache=mode . (mode) all none or pos positive. 2.6.28 . Linux NFS NFS LOOKUP . (positive). (negative). all . pos positive . none . . DATA AND METADATA COHERENCE . fsc / nofsc / ( ) FS-Cache. cachefilesd(8) /Documentation/filesystems/caching FS-Cache. nofsc. sloppy sloppy mount.nfs -s option. xprtsec=policy NFS . (policy) none tls mtls. none NFS . tls RPC-with-TLS . mtls RPC-with-TLS . tls mtls RPC-with-TLS . xprtsec= xprtsec=none. noalignwrite . NFS " " . . 2 3 NFS 2 3 NFS . proto=netid (netid) NFS. udp udp6 tcp tcp6 rdma rdma6. 6 IPv6 TI-RPC . IPv4. retrans timeo . . NFS mount(8) rpcbind mountd . netid TCP mount(8) NFS TCP. netid UDP UDP. NFS UDP TRANSPORT METHODS. proto mount(8) . TRANSPORT METHODS . udp udp proto=udp.. . NFS UDP TRANSPORT METHODS. tcp tcp proto=tcp.. . rdma rdma proto=rdma. port=n NFS . NFS . 0 NFS NFS rpcbind . rpcbind NFS rpcbind NFS . mountport=n mountd . mountd . 0 mount(8) mountd rpcbind . rpcbind mountd rpcbind mountd . NFS rpcbind. mountproto=netid NFS mountd NFS . (netid) udp tcp IPv4 TI-RPC mount.nfs udp6 tcp6 IPv6. NFS . proto mountd NFS. mountd . TRANSPORT METHODS mountproto proto. mounthost=name mountd. mount(8) mountd NFS. mountvers=n RPC mountd . NFS . NFS . namlen=n . . 255 . NFS . pathconf(3) . lock / nolock NLM . ( lock) NLM . nolock . . NLM nolock NFS /var /var NLM . nolock NFS NLM. cto / nocto close-to-open ( ). ( cto) close-to-open. nocto . nocto . . acl / noacl NFSACL . NFSACL . NFSACL NFS . acl noacl NFS NFSACL . NFSACL . . local_lock=mechanism flock POSIX . mechanism all flock posix none. 2.6.37 . Linux NFS . . . none . all flock POSIX . flock flock NLM POSIX. posix POSIX NLM flock. flock NFS 2.6.12 'local_lock=flock'. NFS Samba Samba Windows flock. NFS 2.6.12 flock POSIX . : 'local_lock' 'nolock'/'lock'. 4 NFS 4.0 NFS . proto=netid netid NFS. tcp tcp6 rdma rdma6. tcp6 IPv6 TI-RPC . IPv4. 4 NFS TCP 4 NFS TCP. . minorversion=n . NFSv4 " " NFS NFS. 2.6.38 . "minorversion=1" NFSv4. vers=. vers=4.1 vers=4,minorversion=1. port=n NFS . NFS . NFS NFS 2049 rpcbind . 4 NFS 4 NFS rpcbind. 0 NFS NFS rpcbind . rpcbind NFS rpcbind NFS . cto / nocto close-to-open NFS . cto nocto close-to-open . . . clientaddr=n.n.n.n clientaddr=n:n:...:n IPv4 ( ) IPv6 NFS 4.0 NFS . . IPv4_ANY (0.0.0.0) IPv6 NFS NFS . mount(8) . . . NFS 4.1 4.2 TCP . 4.0 NFS. migration / nomigration NFSv4 (TSM). NFSv4 TSM migration. . nomigration NFS . . . NFSv4 TSM. max_connect=n nconnect IP max_connect IP NFSv4.1+ ( ) 16 . RPC . trunkdiscovery / notrunkdiscovery NFSv4.1+ trunkdiscovery GETATTR fs_locations. EXCHANGE_ID . max_connect. notrunkdiscovery. nfs4 nfs4 NFSv4. NFSv4 nfsvers. /etc/nfsmount.conf. nfsmount.conf(5) . 3 NFS nfs nfsvers=3. 4 NFS nfs nfsvers=4 nfs4. /etc/fstab NFS. server:/export /mnt nfs defaults 0 0 4 NFS TCP Kerberos 5. server:/export /mnt nfs4 sec=krb5 0 0 4 NFS TCP Kerberos 5. server:/export /mnt nfs4 sec=krb5p:krb5i 0 0 /usr NFS. server:/export /usr nfs ro,nolock,nocto,actimeo=3600 0 0 NFS IPv6 . [fe80::215:c5ff:fb3e:e2b1%eth0]:/export /mnt nfs defaults 0 0 NFS NFS RPCs. RPC (endianness) . RPC . mount(8) NFS NFS . . NFS UDP . NFS UDP . NFS . UDP MTU NFS ( jumbo frames). rsize wsize NFS ( ). MTU . TCP NFS . . TCP . NFS . NFS TCP . NFS TCP . ( retrans) . TCP rsize wsize MTU . mountproto 3 NFS 4 NFS . Linux NFS rpcbind NFS mountd (NLM) NFS . Linux NFS proto mountproto udp tcp. (NSM) UDP NSM UDP TCP. NFS (NFSACL) NFS . Linux NFS UDP mountd TCP NLM NFS . mount(8) . . bg . proto udp tcp mountproto mountd NLM NFS. mountproto proto udp tcp mountd NFS TCP . mountproto proto ( udp tcp) mountproto mountd proto ( udp tcp) NFS . . proto udp tcp mountproto . NFS UDP NFS UDP . IP. NFS UDP 4 1500 . IP . IP IP ID 16 UDP IP ID. UDP . . 30 () . 65536 30 . NFS IP 5 . : IP 30 . IP - UDP UDP 16 UDP . UDP 16 1 65536 ( ). . . 100 / IP 30 . NFS TCP TCP . NFS UDP : Jumbo frames: 1500 9000 . (jumbo frames) 9000 NFS UDP 8 . . MTU 9000. Lower reassembly timeout: IP . () /proc/sys/net/ipv4/ipfrag_time. IPID . . NFS . NFS . Close-to-open . . . 3 NFS NFS GETATTR ACCESS. NFS . NFS . NFS close(2). close-to-open CTO. nocto. . 3 NFS " " ( WCC) . . ( ) . noac . . . noac . . noac " ". noac (races) . NFS . . O_DIRECT . NFS (atime ctime mtime). NFS . NFS . NFS NFS. NFS NFS. POSIX Linux NFS NFS mtime ctime . mtime stat(2). atime . NFS atime atime . Linux NFS atime. mount(8) . atime/noatime diratime/nodiratime relatime/norelatime strictatime/nostrictatime NFS. /proc/mounts relatime NFS atime relatime. Linux NFS NFS LOOKUP. . ( ENOENT) . Linux NFS mtime . mtime LOOKUP . mtime . acdirmin acdirmax noac mtime . . . lookupcache . 2.6.28 Linux NFS . . Linux NFS lookupcache=positive. . lookupcache=none. NFS . noac NFS . sync NFS sync ( mount(8) sync async). sync async ( async) NFS : . sync(2) msync(2) fsync(3). close(2). fcntl(2). . sync . . O_SYNC sync. NFS (NLM) NFS 3. -- (NSM). NFS 4 NFS NLM NSM. NLM NSM . NFS NFS . NLM . NFS fcntl(2) F_GETLK F_SETLK. NFS flock(2) . NLM NFS NLM nolock. NLM nolock NFS /var /var NLM . nolock . NFS 4 NFS 4 . NFS 4 : . NFS . . . NFS 4 . ( ) . . : . . . . . . . NFS RPC NFS. NFS . RPC ( uid ) ( gid) 16 . ( " ") . NFS 2 3 . . NFS NFS 4 . NFS 4 RPC. NFS 4 NFS NFS 4 . RPCGSS NFS 2 3 . sec NFS . sec=krb5 RPC. . (Kerberos). rpc.gssd(8) . : krb5i krb5p. krb5i RPC . krb5p RPC . . NFS 4 NFS 4 . . (pseudo-fs) . NFS 4 NFS 4 . . . NFS 4 . . . . nfs4.nfs4_unique_id . . . NFS NFS 4. . . NFS ( /etc/krb5.keytab ) . . host/ nfs/ /etc/krb5.keytab rpc.gssd(8). (keytab) AUTH_SYS 0 . NFS NFS . 1 65535 IP. (TCP UDP) IP . NFS . 1024. (root) . sysctls ssh. NFS . NFS AUTH_SYS UID GID NFS. NFS UID GID NFS . . NFS. . AUTH_SYS NFS. NFS . . . NFS IP. NFS mount(8) NFS. NFS portmapper rpcbind . rpcbind : RPC RPC rpcbind (111) . NFS (2049) NLM . rpcbind . rpcbind NFS NFS . mountd mountport mount(8). TCP UDP . NFS (Solaris) NFS 3 POSIX . NFSACL . Solaris NFS. NFSACL NFS 3. NFS 4 POSIX ACLs. NFS 4 POSIX ACLs POSIX ACLs NFS 4. rw sync NFS remount. mount(8) . NFS . NFS . NFS noac . noac sync NFS actimeo=0. NFS 2 3 NFS umount MNT. NFS . . mount -o remount,ro /mnt ro NFS /mnt. /etc/fstab /etc/nfsmount.conf NFS 2.4.7 NFS NFS TCP. 2.4.20 NFS (close-to-open) . 2.4.22 NFS RTT (Van Jacobsen) NFS UDP. 2.6.0 NFS NFS 4. 2.6.8 NFS rsize wsize . CONFIG_NFS_V2 CONFIG_NFS_V3 CONFIG_NFS_V4 CONFIG_NFS_V4_1 CONFIG_NFS_V4_2. fstab(5), mount(8), umount(8), mount.nfs(5), umount.nfs(5), exports(5), nfsmount.conf(5), netconfig(5), ipv6(7), nfsd(8), sm-notify(8), rpc.statd(8), rpc.idmapd(8), rpc.gssd(8), rpc.svcgssd(8), kerberos(1) RFC 768 UDP. RFC 793 TCP. RFC 1813 NFS 3. RFC 1832 XDR. RFC 1833 RPC. RFC 2203 RPCSEC GSS API. RFC 7530 NFS 4.0. RFC 5661 NFS 4.1. RFC 7862 NFS 4.2. 3 . . : . 9 2012 NFS(5)