X-Git-Url: https://git.decadent.org.uk/gitweb/?p=nfs-utils.git;a=blobdiff_plain;f=utils%2Fmount%2Fnfs.man;h=d92da1905a74a64cdc882e93ac90176abcacce52;hp=614de46764fa19f1a23ee9374f79f9c24eff266d;hb=19517eaaa68af5f299157d07186defa383a18e88;hpb=8539d23dc9f982160bd8f825aa54960e7e1d9d03 diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man index 614de46..d92da19 100644 --- a/utils/mount/nfs.man +++ b/utils/mount/nfs.man @@ -195,11 +195,18 @@ many other operating systems. .TP 1.5i .I nolock Disable NFS locking. Do not start lockd. -This has to be used with some old NFS servers -that don't support locking. Note that applications can -still get locks on files, but the locks only provide exclusion -locally. Other clients mounting the same filesystem -will not be able to detect the locks. +This is appropriate for mounting the root filesystem or +.B /usr +or +.BR /var . +These filesystems are typically either read-only or not shared, and in +those cases, remote locking is not needed. +This also needs to be used with some old NFS servers +that don't support locking. +.br +Note that applications can still get locks on files, but the locks +only provide exclusion locally. Other clients mounting the same +filesystem will not be able to detect the locks. .TP 1.5i .I bg If the first NFS mount attempt times out, retry the mount @@ -276,6 +283,28 @@ support UDP. .TP 1.5i .I udp Mount the NFS filesystem using the UDP protocol. +.TP 1.5i +.I nordirplus +Disables NFSv3 READDIRPLUS RPCs. Use this option when +mounting servers that don't support or have broken +READDIRPLUS implementations. +.TP 1.5i +.I nosharecache +As of kernel 2.6.18, it is no longer possible to mount the same +same filesystem with different mount options to a new mountpoint. +It was deemed unsafe to do so, since cached data cannot be shared +between the two mountpoints. In consequence, files or directories +that were common to both mountpoint subtrees could often be seen to +be out of sync following an update. +.br +This option allows administrators to select the pre-2.6.18 behaviour, +permitting the same filesystem to be mounted with different mount +options. +.br +.B Beware: +Use of this option is not recommended unless you are certain that there +are no hard links or subtrees of this mountpoint that are mounted +elsewhere. .P All of the non-value options have corresponding nooption forms. For example, nointr means don't allow file operations to be @@ -382,11 +411,23 @@ Valid protocol types are and .IR tcp . .TP 1.5i -.I clientaddr=n -On a multi-homed client, this -causes the client to use a specific callback address when -communicating with an NFS version 4 server. -This option is currently ignored. +.I clientaddr=n.n.n.n +Specifies a single IPv4 address in dotted-quad form that +the NFS client advertises to allow servers to perform +NFSv4 callback requests against files on this mount point. +If the server is not able to establish callback connections +to clients, performance may degrade, or accesses to +files may temporarily hang. +.IP +If this option is not specified, the +.BR mount (8) +command attempts to discover an appropriate callback +address automatically. +The automatic discovery process is not perfect, however. +In the presence of multiple client network interfaces, special +routing policies, or atypical network topologies, the exact +address to use for callbacks may be nontrivial to determine, +and should be explicitly set using this mount option. .TP 1.5i .I sec=mode Same as \f3sec=mode\f1 for the nfs filesystem type (see above). @@ -432,6 +473,23 @@ This extracts a server performance penalty but it allows two different NFS clients to get reasonable good results when both clients are actively writing to common filesystem on the server. +.TP 1.5i +.I nosharecache +As of kernel 2.6.18, it is no longer possible to mount the same +same filesystem with different mount options to a new mountpoint. +It was deemed unsafe to do so, since cached data cannot be shared +between the two mountpoints. In consequence, files or directories +that were common to both mountpoint subtrees could often be seen to +be out of sync following an update. +.br +This option allows administrators to select the pre-2.6.18 behaviour, +permitting the same filesystem to be mounted with different mount +options. +.br +.B Beware: +Use of this option is not recommended unless you are certain that there +are no hard links or subtrees of this mountpoint that are mounted +elsewhere. .P All of the non-value options have corresponding nooption forms. For example, nointr means don't allow file operations to be