X-Git-Url: https://git.decadent.org.uk/gitweb/?p=nfs-utils.git;a=blobdiff_plain;f=utils%2Fmount%2Fnfs.man;fp=utils%2Fmount%2Fnfs.man;h=a8ec46cb7509ba85c6d3359f3bc3eb27f7fc47d4;hp=87e27e1519615d3663172dc0b29d7aef33514695;hb=fb06ed9fc1fa11a95544fb2d89adb6c51ef5d946;hpb=5b30c751e3bceab727de684c5ca96c6edd6df001 diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man index 87e27e1..a8ec46c 100644 --- a/utils/mount/nfs.man +++ b/utils/mount/nfs.man @@ -1,5 +1,5 @@ .\"@(#)nfs.5" -.TH NFS 5 "2 November 2007" +.TH NFS 5 "9 October 2012" .SH NAME nfs \- fstab format and options for the .B nfs @@ -347,6 +347,13 @@ using an automounter (refer to .BR automount (8) for details). .TP 1.5i +.BR rdirplus " / " nordirplus +Selects whether to use NFS v3 or v4 READDIRPLUS requests. +If this option is not specified, the NFS client uses READDIRPLUS requests +on NFS v3 or v4 mounts to read small directories. +Some applications perform better if the client uses only READDIR requests +for all directories. +.TP 1.5i .BI retry= n The number of minutes that the .BR mount (8) @@ -359,21 +366,22 @@ If a value of zero is specified, the .BR mount (8) command exits immediately after the first failure. .TP 1.5i -.BI sec= mode -The RPCGSS security flavor to use for accessing files on this mount point. -If the -.B sec -option is not specified, or if -.B sec=sys -is specified, the NFS client uses the AUTH_SYS security flavor -for all NFS requests on this mount point. -Valid security flavors are +.BI sec= flavor +The security flavor to use for accessing files on this mount point. +If the server does not support this flavor, the mount operation fails. +If +.B sec= +is not specified, the client attempts to find +a security flavor that both the client and the server supports. +Valid +.I flavors +are .BR none , .BR sys , .BR krb5 , .BR krb5i , and -.BR krb5p , +.BR krb5p . Refer to the SECURITY CONSIDERATIONS section for details. .TP 1.5i .BR sharecache " / " nosharecache @@ -460,29 +468,27 @@ by other clients, but can impact application and server performance. .IP The DATA AND METADATA COHERENCE section contains a detailed discussion of these trade-offs. +.TP 1.5i +.BR fsc " / " nofsc +Enable/Disables the cache of (read-only) data pages to the local disk +using the FS-Cache facility. See cachefilesd(8) +and /Documentation/filesystems/caching +for detail on how to configure the FS-Cache facility. +Default value is nofsc. .SS "Options for NFS versions 2 and 3 only" Use these options, along with the options in the above subsection, for NFS versions 2 and 3 only. .TP 1.5i .BI proto= netid -The transport protocol name and protocol family the NFS client uses -to transmit requests to the NFS server for this mount point. -If an NFS server has both an IPv4 and an IPv6 address, using a specific -netid will force the use of IPv4 or IPv6 networking to communicate -with that server. -.IP -If support for TI-RPC is built into the -.B mount.nfs -command, -.I netid -is a valid netid listed in -.IR /etc/netconfig . -The value "rdma" may also be specified. -If the -.B mount.nfs -command does not have TI-RPC support, then +The .I netid -is one of "tcp," "udp," or "rdma," and only IPv4 may be used. +determines the transport that is used to communicate with the NFS +server. Available options are +.BR udp ", " udp6 ", "tcp ", " tcp6 ", and " rdma . +Those which end in +.B 6 +use IPv6 addresses and are only available if support for TI-RPC is +built in. Others use IPv4 addresses. .IP Each transport protocol uses different default .B retrans @@ -562,19 +568,18 @@ This option can be used when mounting an NFS server through a firewall that blocks the rpcbind protocol. .TP 1.5i .BI mountproto= netid -The transport protocol name and protocol family the NFS client uses +The transport the NFS client uses to transmit requests to the NFS server's mountd service when performing this mount request, and when later unmounting this mount point. .IP -If support for TI-RPC is built into the +.I netid +may be one of +.BR udp ", and " tcp +which use IPv4 address or, if TI-RPC is built into the .B mount.nfs command, -.I netid -is a valid netid listed in -.IR /etc/netconfig . -Otherwise, -.I netid -is one of "tcp" or "udp," and only IPv4 may be used. +.BR udp6 ", and " tcp6 +which use IPv6 addresses. .IP This option can be used when mounting an NFS server through a firewall that blocks a particular transport. @@ -711,13 +716,6 @@ Disabling the NFSACL sideband protocol may be necessary if the negotiation causes problems on the client or server. Refer to the SECURITY CONSIDERATIONS section for more details. .TP 1.5i -.BR rdirplus " / " nordirplus -Selects whether to use NFS version 3 READDIRPLUS requests. -If this option is not specified, the NFS client uses READDIRPLUS requests -on NFS version 3 mounts to read small directories. -Some applications perform better if the client uses only READDIR requests -for all directories. -.TP 1.5i .BR local_lock= mechanism Specifies whether to use local locking for any or both of the flock and the POSIX locking mechanisms. @@ -766,21 +764,14 @@ Use these options, along with the options in the first subsection above, for NFS version 4 and newer. .TP 1.5i .BI proto= netid -The transport protocol name and protocol family the NFS client uses -to transmit requests to the NFS server for this mount point. -If an NFS server has both an IPv4 and an IPv6 address, using a specific -netid will force the use of IPv4 or IPv6 networking to communicate -with that server. -.IP -If support for TI-RPC is built into the -.B mount.nfs -command, -.I netid -is a valid netid listed in -.IR /etc/netconfig . -Otherwise, +The .I netid -is one of "tcp" or "udp," and only IPv4 may be used. +determines the transport that is used to communicate with the NFS +server. Supported options are +.BR tcp ", " tcp6 ", and " rdma . +.B tcp6 +use IPv6 addresses and is only available if support for TI-RPC is +built in. Both others use IPv4 addresses. .IP All NFS version 4 servers are required to support TCP, so if this mount option is not specified, the NFS version 4 client @@ -844,6 +835,8 @@ The DATA AND METADATA COHERENCE section discusses the behavior of this option in more detail. .TP 1.5i .BI clientaddr= n.n.n.n +.TP 1.5i +.BI clientaddr= n:n: ... :n Specifies a single IPv4 address (in dotted-quad form), or a non-link-local IPv6 address, that the NFS client advertises to allow servers @@ -1452,19 +1445,19 @@ These auxiliary protocols use no authentication. In addition to combining these sideband protocols with the main NFS protocol, NFS version 4 introduces more advanced forms of access control, authentication, and in-transit data protection. -The NFS version 4 specification mandates NFSv4 ACLs, -RPCGSS authentication, and RPCGSS security flavors +The NFS version 4 specification mandates support for +strong authentication and security flavors that provide per-RPC integrity checking and encryption. Because NFS version 4 combines the function of the sideband protocols into the main NFS protocol, the new security features apply to all NFS version 4 operations including mounting, file locking, and so on. RPCGSS authentication can also be used with NFS versions 2 and 3, -but does not protect their sideband protocols. +but it does not protect their sideband protocols. .P The .B sec -mount option specifies the RPCGSS security mode +mount option specifies the security flavor that is in effect on a given NFS mount point. Specifying .B sec=krb5 @@ -1495,13 +1488,14 @@ Similar support for other forms of cryptographic security is also available. .P The NFS version 4 protocol allows -clients and servers to negotiate among multiple security flavors -during mount processing. -However, Linux does not yet implement such negotiation. -The Linux client specifies a single security flavor at mount time -which remains in effect for the lifetime of the mount. -If the server does not support this flavor, -the initial mount request is rejected by the server. +a client to renegotiate the security flavor +when the client crosses into a new filesystem on the server. +The newly negotiated flavor effects only accesses of the new filesystem. +.P +Such negotiation typically occurs when a client crosses +from a server's pseudo-fs +into one of the server's exported physical filesystems, +which often have more restrictive security settings than the pseudo-fs. .SS "Using non-privileged source ports" NFS clients usually communicate with NFS servers via network sockets. Each end of a socket is assigned a port value, which is simply a number