.BI timeo= n
The time (in tenths of a second) the NFS client waits for a
response before it retries an NFS request. If this
-option is not specified, requests are retried after
-60 seconds for NFS over TCP, and are retried after 7/10 of a second for
-NFS over UDP.
+option is not specified, requests are retried every
+60 seconds for NFS over TCP.
+The NFS client does not perform any kind of timeout backoff
+for NFS over TCP.
.IP
-For NFS over TCP, the client uses a fixed timeout, as specified by the
-.B timeo
-option. However, for NFS over UDP, the client uses an adaptive
+However, for NFS over UDP, the client uses an adaptive
algorithm to estimate an appropriate timeout value for frequently used
request types (such as READ and WRITE requests), but uses the
.B timeo
setting for infrequently used request types (such as FSINFO requests).
-After each retransmission, the NFS client doubles the timeout for that
-request, up to a maximum timeout length of 60 seconds.
+If the
+.B timeo
+option is not specified,
+infrequently used request types are retried after 1.1 seconds.
+After each retransmission, the NFS client doubles the timeout for
+that request,
+up to a maximum timeout length of 60 seconds.
.TP 1.5i
.BI retrans= n
The number of times the NFS client retries a request before
it attempts further recovery action. If the
.B retrans
-option is not specified, the NFS client retries each request
+option is not specified, the NFS client tries each request
three times.
.IP
The NFS client generates a "server not responding" message
.B nfs
file system type.
.TP 1.5i
-.BI proto= netid
-The transport protocol used by the NFS client
+.BI proto= transport
+The transport the NFS client uses
to transmit requests to the NFS server for this mount point.
-.I netid
+.I transport
can be either
.B udp
or
.BR tcp .
-Each transport protocol uses different default
+Each transport uses different default
.B retrans
and
.B timeo
This option can be used when mounting an NFS server
through a firewall that blocks the rpcbind protocol.
.TP 1.5i
+.BI mountproto= transport
+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.
+.I transport
+can be either
+.B udp
+or
+.BR tcp .
+.IP
+This option can be used when mounting an NFS server
+through a firewall that blocks a particular transport.
+When used in combination with the
+.B proto
+option, different transports for mountd requests and NFS requests
+can be specified.
+If the server's mountd service is not available via the specified
+transport, the mount request fails.
+.TP 1.5i
.BI mounthost= name
The hostname of the host running mountd.
If this option is not specified, the
.B nfs4
file system type.
.TP 1.5i
-.BI proto= netid
-The transport protocol used by the NFS client
+.BI proto= transport
+The transport the NFS client uses
to transmit requests to the NFS server for this mount point.
-.I netid
+.I transport
can be either
.B udp
or