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@(#)tftp.1 8.2 (Berkeley) 4/18/94
.Dd July 23, 2006 .Dt TFTP 1 .Os .Sh NAME .Nm tftp .Nd trivial file transfer program .Sh SYNOPSIS .Nm .Op Fl e .Op Ar host .Op Ar port .Sh DESCRIPTION .Nm is the user interface to the Internet .Tn TFTP (Trivial File Transfer Protocol), which allows users to transfer files to and from a remote machine. The remote .Ar host (and optional .Ar port ) may be specified on the command line, in which case .Nm uses .Ar host (and .Ar port ) as the default for future transfers (see the .Cm connect command below).
p The optional .Fl e argument sets a binary transfer mode as well as setting the extended options as if .Cm tout , .Cm tsize , and .Cm blksize 65464 , had been given.
p The Multicast TFTP option is supported in open-loop (i.e., "slave-only") mode based on IETF draft-dion-tftp-multicast-option-01.txt (May 2002), which in turn was based on RFC2026. .Sh COMMANDS Once .Nm is running, it issues the prompt .Ql tftp> and recognizes the following commands:
p l -tag -width verbose -compact t Cm ? Ar command-name ... Print help information.
p t Cm ascii Shorthand for "mode ascii"
p t Cm binary Shorthand for "mode binary"
p t Cm blksize Ar blk-size Set the tftp blksize option to .Ar blk-size octets (8-bit bytes). Since the number of blocks in a tftp .Cm get or .Cm put is 65535, the default block size of 512 bytes only allows a maximum of just under 32 megabytes to be transferred. The value given for .Ar blk-size must be between 8 and 65464, inclusive. Note that many servers will not respect this option.
p t Cm connect Ar host-name Op Ar port Set the .Ar host (and optionally .Ar port ) for transfers. Note that the .Tn TFTP protocol, unlike the .Tn FTP protocol, does not maintain connections between transfers; thus, the .Cm connect command does not actually create a connection, but merely remembers what host is to be used for transfers. You do not have to use the .Cm connect command; the remote host can be specified as part of the .Cm get or .Cm put commands.
p t Cm get Ar filename t Cm get Ar remotename localname t Cm get Ar file1 file2 ... fileN Get a file or set of files from the specified .Ar sources . .Ar Source can be in one of two forms: a filename on the remote host, if the host has already been specified, or a string of the form .Ar hosts:filename to specify both a host and filename at the same time. If the latter form is used, the last hostname specified becomes the default for future transfers.
p t Cm mode Ar transfer-mode Set the mode for transfers; .Ar transfer-mode may be one of .Em ascii or .Em binary . The default is .Em ascii .
p t Cm put Ar file t Cm put Ar localfile remotefile t Cm put Ar file1 file2 ... fileN remote-directory Put a file or set of files to the specified remote file or directory. The destination can be in one of two forms: a filename on the remote host, if the host has already been specified, or a string of the form .Ar hosts:filename to specify both a host and filename at the same time. If the latter form is used, the hostname specified becomes the default for future transfers. If the remote-directory form is used, the remote host is assumed to be a x machine. If you need to specify IPv6 numeric address to .Ar hosts , wrap them using square bracket like .Ar [hosts]:filename to disambiguate the colon.
p t Cm quit Exit .Nm . An end of file also exits.
p t Cm rexmt Ar retransmission-timeout Set the per-packet retransmission timeout, in seconds.
p t Cm status Show current status.
p t Cm timeout Ar total-transmission-timeout Set the total transmission timeout, in seconds.
p t Cm tout Toggle the tftp "timeout" option. If enabled, the client will pass its .Ar retransmission-timeout to the server. Note that many servers will not respect this option.
p t Cm trace Toggle packet tracing.
p t Cm tsize Toggle the tftp "tsize" option. If enabled, the client will pass and request the filesize of a file at the beginning of a file transfer. Note that many servers will not respect this option.
p t Cm verbose Toggle verbose mode. .El .Sh HISTORY The .Nm command appeared in x 4.3 . IPv6 support was implemented by WIDE/KAME project in 1999. TFTP options were implemented by Wasabi Systems, Inc., in 2003, and first appeared in .Nx 2.0 . Multicast TFTP was implemented by .An Jared D. McNeill in 2006, and first appeared in .Nx 4.0 . .Sh SECURITY CONSIDERATIONS Because there is no user-login or validation within the .Tn TFTP protocol, the remote site will probably have some sort of file-access restrictions in place. The exact methods are specific to each site and therefore difficult to document here.
Indexes created Mon Sep 22 13:09:51 GMT 2025