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mount_nfs Mounts NFS file systems.
mount_nfs [-23KPTUbcdilqs] [-D <deadthresh>] [-I <readdirsize>] [-L
<leaseterm>] [-R <retrycnt>] [-a <maxreadahead>] [-g <maxgroups>] [-m
<realm>] [-o <optsions>] [-r <readsize>] [-t <timeout>] [-w <writesize>]
[-x <retrans>] <rhost>:<path> <node>

-2 Uses NFS Version 2 protocol.
-3 Uses NFS Version 3 protocol. Default is to try version 3 first and fall back to version 2 if the mount fails.
-K Passes Kerberos authentication to the server for client-to-server user-credential mapping. This requires that the kernel be built with the NFSKERB option.
-P The kernel uses a reserved port number to communicate with clients. This option is ignored and exits for compatibility with older systems.
-T Uses TCP transport instead of UDP. This is recommended for servers that are not on the same LAN cable as the client. This is not supported by most non-BSD servers.
-U Forces the mount protocol to use UDP transport, even for TCP NFS mounts. Necessary for some old BSD servers.
-b Backgrounds the mount. If a mount fails, forks a child process that keeps trying the mount in the background. This option is useful for a file system that is not critical to multiuser operation.
-c Does not do a connect (2) for UDP mounts. This must be used for servers that do not reply to requests from the standard NFS port number 2049. It may also be required for servers with more than one IP address, if replies come from an address other than the one specified in the mount request.
-d Turns off the dynamic retransmit timeout estimator. This may be useful for UDP mounts that exhibit high retry rates; it is possible for the dynamically estimated timeout to be too short.
-i Makes the mount interruptible. The file system calls that are delayed due to an unresponsive server fail with EINTR when a termination signal is posted for the process.
-l Used with NQNFS and NFSV3 to specify that the ReaddirPlus RPC should be used. This option reduces RPC traffic for cases such as ls -l, but floods the attribute and name caches with preferred entries. Probably most useful for client to server network interconnects with a large bandwidth * delay product.
-q Uses the leasing extensions to NFSV3 to maintain cache consistency. This protocol version 2 revision to Not Quite NFS (NQNFS) is only supported by this updated release of NFS code. It is not backward compatible to the version 1 NQNFS protocol that was part of the first release of 4.4 BSD-Lite.
-s Soft mount. File system calls fail after retry round trip timeout intervals.
-D <deadthresh> Used with NQNFS to set the dead server threshold to <deadthresh> number of round trip timeout intervals. After <deadthresh> retransmit timeouts, cached data for the unresponsive server is assumed to still be valid. Values may be set in the range of 1–9, with 9 being an infinite dead threshold that never assumes cached data is still valid. This option is not generally recommended and is still experimental.
-I <readdirsize> Sets the readdir read size to <readdirsize>. The value should normally be a multiple of DIRBLKSIZ that is <= the read size for the mount.
-L <leaseterm> Used with NQNFS to set the lease term to <leaseterm> seconds. Only use this option for mounts with a large round-trip delay. Values are normally in the 10–30 seconds range.
-R <retrycnt> Sets the retry count for doing the mount to <retrycnt>.
-a <maxreadahead> Sets the read-ahead count to <maxreadahead>. This value may be in the 0–4 range, and determines how many blocks are read ahead when a large file is being read sequentially. A value larger than 1 is suggested for mounts with a large bandwidth * delay product.
-g <maxgroups> Sets the maximum size of the group list for the credentials to <maxgroups>. This should be used for mounts on old servers that cannot handle a group list size of 16, as specified in RFC 1057. Try 8 if users in a log of groups cannot get a response from the mount point.
-m <realm> Sets the Kerberos real to the string argument <realm>. Used with the -K option for mounts to other realms.
-o <options> Options are specified as a comma-separated list of options. See mount (8) for a listing of the available options.
-r <readsize> Sets the read data size to <readsize>. It should normally be a power of 2 >= 1024. This should be used for UDP mounts when the fragments dropped due to timeout value are getting large while actively using a mount point. Use netstat (1) -s to get the fragments dropped due to timeout value. See -w option.
-t <timeout> Sets the initial retransmit timeout to <timeout>. May be useful for fine-tuning UDP mounts over networks with high packet loss rates or an overloaded server. Try increasing the interval if nfsstat (1) shows high retransmit rates while the file system is active or reducing the value if there is a low retransmit rate but long response delay observed. Normally the -d option is also used when using this option to fine-tune the timeout interval.
-w <writesize> Sets the write data size to <writesize>. See comments regarding the -r option, but using the fragments dropped due to timeout value on the server rather than the client. The -r and -w options should only be used as a last resort to improve performance when mounting servers that do not support TCP mounts.
-x <retrans> Sets the retransmit timeout count for soft mounts to <retrans>.



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