The Tahoe-LAFS CLI commands¶
- Overview
- CLI Command Overview
- Node Management
- Filesystem Manipulation
- Storage Grid Maintenance
- Debugging
Overview¶
Tahoe-LAFS provides a single executable named “tahoe
”, which can be used
to create and manage client/server nodes, manipulate the filesystem, and
perform several debugging/maintenance tasks. This executable is installed
into your virtualenv when you run pip install tahoe-lafs
.
CLI Command Overview¶
The “tahoe
” tool provides access to three categories of commands.
- node management: create a client/server node, start/stop/restart it
- filesystem manipulation: list files, upload, download, unlink, rename
- debugging: unpack cap-strings, examine share files
To get a list of all commands, just run “tahoe
” with no additional
arguments. “tahoe --help
” might also provide something useful.
Running “tahoe --version
” will display a list of version strings, starting
with the “allmydata” module (which contains the majority of the Tahoe-LAFS
functionality) and including versions for a number of dependent libraries,
like Twisted, Foolscap, pycryptopp, and zfec. “tahoe --version-and-path
”
will also show the path from which each library was imported.
On Unix systems, the shell expands filename wildcards ('*'
and '?'
)
before the program is able to read them, which may produce unexpected results
for many tahoe
comands. We recommend, if you use wildcards, to start the
path with “./
”, for example “tahoe cp -r ./* somewhere:
”. This
prevents the expanded filename from being interpreted as an option or as an
alias, allowing filenames that start with a dash or contain colons to be
handled correctly.
On Windows, a single letter followed by a colon is treated as a drive
specification rather than an alias (and is invalid unless a local path is
allowed in that context). Wildcards cannot be used to specify multiple
filenames to tahoe
on Windows.
Unicode Support¶
As of Tahoe-LAFS v1.7.0 (v1.8.0 on Windows), the tahoe
tool supports
non-ASCII characters in command lines and output. On Unix, the command-line
arguments are assumed to use the character encoding specified by the
current locale (usually given by the LANG
environment variable).
If a name to be output contains control characters or characters that cannot be represented in the encoding used on your terminal, it will be quoted. The quoting scheme used is similar to POSIX shell quoting: in a “double-quoted” string, backslashes introduce escape sequences (like those in Python strings), but in a ‘single-quoted’ string all characters stand for themselves. This quoting is only used for output, on all operating systems. Your shell interprets any quoting or escapes used on the command line.
Node Management¶
“tahoe create-node [NODEDIR]
” is the basic make-a-new-node command. It
creates a new directory and populates it with files that will allow the
“tahoe start
” command to use it later on. This command creates nodes that
have client functionality (upload/download files), web API services
(controlled by the ‘[node]web.port’ configuration), and storage services
(unless --no-storage
is specified).
NODEDIR defaults to ~/.tahoe/
, and newly-created nodes default to
publishing a web server on port 3456 (limited to the loopback interface, at
127.0.0.1, to restrict access to other programs on the same host). All of the
other “tahoe
” subcommands use corresponding defaults (with the exception
that “tahoe run
” defaults to running a node in the current directory).
“tahoe create-client [NODEDIR]
” creates a node with no storage service.
That is, it behaves like “tahoe create-node --no-storage [NODEDIR]
”.
(This is a change from versions prior to v1.6.0.)
“tahoe create-introducer [NODEDIR]
” is used to create the Introducer node.
This node provides introduction services and nothing else. When started, this
node will produce a private/introducer.furl
file, which should be
published to all clients.
“tahoe run [NODEDIR]
” will start a previously-created node in the foreground.
“tahoe start [NODEDIR]
” will launch a previously-created node. It will
launch the node into the background, using the standard Twisted “twistd
”
daemon-launching tool. On some platforms (including Windows) this command is
unable to run a daemon in the background; in that case it behaves in the
same way as “tahoe run
”.
“tahoe stop [NODEDIR]
” will shut down a running node.
“tahoe restart [NODEDIR]
” will stop and then restart a running node. This
is most often used by developers who have just modified the code and want to
start using their changes.
Filesystem Manipulation¶
These commands let you exmaine a Tahoe-LAFS filesystem, providing basic list/upload/download/unlink/rename/mkdir functionality. They can be used as primitives by other scripts. Most of these commands are fairly thin wrappers around web-API calls, which are described in The Tahoe REST-ful Web API.
By default, all filesystem-manipulation commands look in ~/.tahoe/
to
figure out which Tahoe-LAFS node they should use. When the CLI command makes
web-API calls, it will use ~/.tahoe/node.url
for this purpose: a running
Tahoe-LAFS node that provides a web-API port will write its URL into this
file. If you want to use a node on some other host, just create ~/.tahoe/
and copy that node’s web-API URL into this file, and the CLI commands will
contact that node instead of a local one.
These commands also use a table of “aliases” to figure out which directory they ought to use a starting point. This is explained in more detail below.
Starting Directories¶
As described in Tahoe-LAFS Architecture, the Tahoe-LAFS distributed filesystem consists of a collection of directories and files, each of which has a “read-cap” or a “write-cap” (also known as a URI). Each directory is simply a table that maps a name to a child file or directory, and this table is turned into a string and stored in a mutable file. The whole set of directory and file “nodes” are connected together into a directed graph.
To use this collection of files and directories, you need to choose a
starting point: some specific directory that we will refer to as a
“starting directory”. For a given starting directory, the
“ls [STARTING_DIR]
” command would list the contents of this directory,
the “ls [STARTING_DIR]/dir1
” command would look inside this directory
for a child named “dir1
” and list its contents,
“ls [STARTING_DIR]/dir1/subdir2
” would look two levels deep, etc.
Note that there is no real global “root” directory, but instead each starting directory provides a different, possibly overlapping perspective on the graph of files and directories.
Each Tahoe-LAFS node remembers a list of starting points, called “aliases”,
which are short Unicode strings that stand in for a directory read- or
write- cap. They are stored (encoded as UTF-8) in the file
NODEDIR/private/aliases
. If you use the command line “tahoe ls
”
without any “[STARTING_DIR]” argument, then it will use the default alias,
which is tahoe:
, therefore “tahoe ls
” has the same effect as
“tahoe ls tahoe:
”. The same goes for the other commands that can
reasonably use a default alias: get
, put
, mkdir
, mv
, and
rm
.
For backwards compatibility with Tahoe-LAFS v1.0, if the tahoe:
alias
is not found in ~/.tahoe/private/aliases
, the CLI will use the contents
of ~/.tahoe/private/root_dir.cap
instead. Tahoe-LAFS v1.0 had only a
single starting point, and stored it in this root_dir.cap
file, so v1.1
and later will use it if necessary. However, once you’ve set a tahoe:
alias with “tahoe set-alias
”, that will override anything in the old
root_dir.cap
file.
The Tahoe-LAFS CLI commands use the same path syntax as scp
and
rsync
– an optional ALIAS:
prefix, followed by the pathname or
filename. Some commands (like “tahoe cp
”) use the lack of an alias to
mean that you want to refer to a local file, instead of something from the
Tahoe-LAFS filesystem. Another way to indicate this is to start the
pathname with ”./”, “~/”, “~username/”, or “/”.
When you’re dealing a single starting directory, the tahoe:
alias is
all you need. But when you want to refer to something that isn’t yet
attached to the graph rooted at that starting directory, you need to
refer to it by its capability. The way to do that is either to use its
capability directory as an argument on the command line, or to add an
alias to it, with the “tahoe add-alias
” command. Once you’ve added an
alias, you can use that alias as an argument to commands.
The best way to get started with Tahoe-LAFS is to create a node, start it,
then use the following command to create a new directory and set it as your
tahoe:
alias:
tahoe create-alias tahoe
After that you can use “tahoe ls tahoe:
” and
“tahoe cp local.txt tahoe:
”, and both will refer to the directory that
you’ve just created.
Command Syntax Summary¶
tahoe add-alias ALIAS[:] DIRCAP
tahoe create-alias ALIAS[:]
tahoe list-aliases
tahoe mkdir
tahoe mkdir PATH
tahoe ls [PATH]
tahoe webopen [PATH]
tahoe put [--mutable] [FROMLOCAL|-]
tahoe put [--mutable] FROMLOCAL|- TOPATH
tahoe put [FROMLOCAL|-] mutable-file-writecap
tahoe get FROMPATH [TOLOCAL|-]
tahoe cp [-r] FROMPATH TOPATH
tahoe rm PATH
tahoe mv FROMPATH TOPATH
tahoe ln FROMPATH TOPATH
tahoe backup FROMLOCAL TOPATH
In these summaries, PATH
, TOPATH
or FROMPATH
can be one of:
[SUBDIRS/]FILENAME
for a path relative to the defaulttahoe:
alias;ALIAS:[SUBDIRS/]FILENAME
for a path relative to another alias;DIRCAP/[SUBDIRS/]FILENAME
orDIRCAP:./[SUBDIRS/]FILENAME
for a path relative to a directory cap.
See CLI Command Overview above for information on using wildcards with local paths, and different treatment of colons between Unix and Windows.
FROMLOCAL
or TOLOCAL
is a path in the local filesystem.
Command Examples¶
tahoe add-alias ALIAS[:] DIRCAP
An example would be:
tahoe add-alias fun URI:DIR2:ovjy4yhylqlfoqg2vcze36dhde:4d4f47qko2xm5g7osgo2yyidi5m4muyo2vjjy53q4vjju2u55mfaThis creates an alias
fun:
and configures it to use the given directory cap. Once this is done, “tahoe ls fun:
” will list the contents of this directory. Use “tahoe add-alias tahoe DIRCAP
” to set the contents of the defaulttahoe:
alias.Since Tahoe-LAFS v1.8.2, the alias name can be given with or without the trailing colon.
On Windows, the alias should not be a single character, because it would be confused with the drive letter of a local path.
tahoe create-alias fun
This combines “tahoe mkdir
” and “tahoe add-alias
” into a single step.
tahoe list-aliases
This displays a table of all configured aliases.
tahoe mkdir
This creates a new empty unlinked directory, and prints its write-cap to stdout. The new directory is not attached to anything else.
tahoe mkdir subdir
tahoe mkdir /subdir
This creates a new empty directory and attaches it below the root directory of the defaulttahoe:
alias with the name “subdir
”.
tahoe ls
tahoe ls /
tahoe ls tahoe:
tahoe ls tahoe:/
All four list the root directory of the defaulttahoe:
alias.
tahoe ls subdir
This lists a subdirectory of your filesystem.
tahoe webopen
tahoe webopen tahoe:
tahoe webopen tahoe:subdir/
tahoe webopen subdir/
This uses the python ‘webbrowser’ module to cause a local web browser to open to the web page for the given directory. This page offers interfaces to add, download, rename, and unlink files and subdirectories in that directory. If no alias or path is given, this command opens the root directory of the defaulttahoe:
alias.
tahoe put file.txt
tahoe put ./file.txt
tahoe put /tmp/file.txt
tahoe put ~/file.txt
These upload the local file into the grid, and prints the new read-cap to stdout. The uploaded file is not attached to any directory. All one-argument forms of “tahoe put
” perform an unlinked upload.
tahoe put -
tahoe put
These also perform an unlinked upload, but the data to be uploaded is taken from stdin.
tahoe put file.txt uploaded.txt
tahoe put file.txt tahoe:uploaded.txt
These upload the local file and add it to yourtahoe:
root with the name “uploaded.txt
”.
tahoe put file.txt subdir/foo.txt
tahoe put - subdir/foo.txt
tahoe put file.txt tahoe:subdir/foo.txt
tahoe put file.txt DIRCAP/foo.txt
tahoe put file.txt DIRCAP/subdir/foo.txt
These upload the named file and attach them to a subdirectory of the given root directory, under the name “foo.txt
”. When a directory write-cap is given, you can use either/
(as shown above) or:./
to separate it from the following path. When the source file is named “-
”, the contents are taken from stdin.
tahoe put file.txt --mutable
Create a new (SDMF) mutable file, fill it with the contents offile.txt
, and print the new write-cap to stdout.
tahoe put file.txt MUTABLE-FILE-WRITECAP
Replace the contents of the given mutable file with the contents offile.txt
and print the same write-cap to stdout.
tahoe cp file.txt tahoe:uploaded.txt
tahoe cp file.txt tahoe:
tahoe cp file.txt tahoe:/
tahoe cp ./file.txt tahoe:
These upload the local file and add it to yourtahoe:
root with the name “uploaded.txt
”.
tahoe cp tahoe:uploaded.txt downloaded.txt
tahoe cp tahoe:uploaded.txt ./downloaded.txt
tahoe cp tahoe:uploaded.txt /tmp/downloaded.txt
tahoe cp tahoe:uploaded.txt ~/downloaded.txt
This downloads the named file from yourtahoe:
root, and puts the result on your local filesystem.
tahoe cp tahoe:uploaded.txt fun:stuff.txt
This copies a file from your
tahoe:
root to a different directory, set up earlier with “tahoe add-alias fun DIRCAP
” or “tahoe create-alias fun
”.
tahoe cp -r ~/my_dir/ tahoe:
This copies the folder
~/my_dir/
and all its children to the grid, creating the new foldertahoe:my_dir
. Note that the trailing slash is not required: all source arguments which are directories will be copied into new subdirectories of the target.The behavior of
tahoe cp
, like the regular UNIX/bin/cp
, is subtly different depending upon the exact form of the arguments. In particular:
- Trailing slashes indicate directories, but are not required.
- If the target object does not already exist: * and if the source is a single file, it will be copied into the target; * otherwise, the target will be created as a directory.
- If there are multiple sources, the target must be a directory.
- If the target is a pre-existing file, the source must be a single file.
- If the target is a directory, each source must be a named file, a named directory, or an unnamed directory. It is not possible to copy an unnamed file (e.g. a raw filecap) into a directory, as there is no way to know what the new file should be named.
tahoe unlink uploaded.txt
tahoe unlink tahoe:uploaded.txt
This unlinks a file from yourtahoe:
root (that is, causes there to no longer be an entryuploaded.txt
in the root directory that points to it). Note that this does not delete the file from the grid. For backward compatibility,tahoe rm
is accepted as a synonym fortahoe unlink
.
tahoe mv uploaded.txt renamed.txt
tahoe mv tahoe:uploaded.txt tahoe:renamed.txt
These rename a file within yourtahoe:
root directory.
tahoe mv uploaded.txt fun:
tahoe mv tahoe:uploaded.txt fun:
tahoe mv tahoe:uploaded.txt fun:uploaded.txt
These move a file from yourtahoe:
root directory to the directory set up earlier with “tahoe add-alias fun DIRCAP
” or “tahoe create-alias fun
”.
tahoe backup ~ work:backups
This command performs a versioned backup of every file and directory underneath your “
~
” home directory, placing an immutable timestamped snapshot in e.g.work:backups/Archives/2009-02-06_04:00:05Z/
(note that the timestamp is in UTC, hence the “Z” suffix), and a link to the latest snapshot in work:backups/Latest/ . This command uses a small SQLite database known as the “backupdb”, stored in~/.tahoe/private/backupdb.sqlite
, to remember which local files have been backed up already, and will avoid uploading files that have already been backed up (except occasionally that will randomly upload them again if it has been awhile since had last been uploaded, just to make sure that the copy of it on the server is still good). It compares timestamps and filesizes when making this comparison. It also re-uses existing directories which have identical contents. This lets it run faster and reduces the number of directories created.If you reconfigure your client node to switch to a different grid, you should delete the stale backupdb.sqlite file, to force “
tahoe backup
” to upload all files to the new grid.The fact that “tahoe backup” checks timestamps on your local files and skips ones that don’t appear to have been changed is one of the major differences between “tahoe backup” and “tahoe cp -r”. The other major difference is that “tahoe backup” keeps links to all of the versions that have been uploaded to the grid, so you can navigate among old versions stored in the grid. In contrast, “tahoe cp -r” unlinks the previous version from the grid directory and links the new version into place, so unless you have a link to the older version stored somewhere else, you’ll never be able to get back to it.
tahoe backup --exclude=*~ ~ work:backups
Same as above, but this time the backup process will ignore any filename that will end with ‘~’.--exclude
will accept any standard Unix shell-style wildcards, as implemented by the Python fnmatch module. You may give multiple--exclude
options. Please pay attention that the pattern will be matched against any level of the directory tree; it’s still impossible to specify absolute path exclusions.
tahoe backup --exclude-from=/path/to/filename ~ work:backups
--exclude-from
is similar to--exclude
, but reads exclusion patterns from/path/to/filename
, one per line.
tahoe backup --exclude-vcs ~ work:backups
This command will ignore any file or directory name known to be used by version control systems to store metadata. The excluded names are:
- CVS
- RCS
- SCCS
- .git
- .gitignore
- .cvsignore
- .svn
- .arch-ids
- {arch}
- =RELEASE-ID
- =meta-update
- =update
- .bzr
- .bzrignore
- .bzrtags
- .hg
- .hgignore
- _darcs
Storage Grid Maintenance¶
tahoe manifest tahoe:
tahoe manifest --storage-index tahoe:
tahoe manifest --verify-cap tahoe:
tahoe manifest --repair-cap tahoe:
tahoe manifest --raw tahoe:
This performs a recursive walk of the given directory, visiting every file and directory that can be reached from that point. It then emits one line to stdout for each object it encounters.
The default behavior is to print the access cap string (like
URI:CHK:..
orURI:DIR2:..
), followed by a space, followed by the full path name.If
--storage-index
is added, each line will instead contain the object’s storage index. This (string) value is useful to determine which share files (on the server) are associated with this directory tree. The--verify-cap
and--repair-cap
options are similar, but emit a verify-cap and repair-cap, respectively. If--raw
is provided instead, the output will be a JSON-encoded dictionary that includes keys for pathnames, storage index strings, and cap strings. The last line of the--raw
output will be a JSON encoded deep-stats dictionary.
tahoe stats tahoe:
This performs a recursive walk of the given directory, visiting every file and directory that can be reached from that point. It gathers statistics on the sizes of the objects it encounters, and prints a summary to stdout.
Debugging¶
For a list of all debugging commands, use “tahoe debug
”. For more detailed
help on any of these commands, use “tahoe debug COMMAND --help
”.
“tahoe debug find-shares STORAGEINDEX NODEDIRS..
” will look through one or
more storage nodes for the share files that are providing storage for the
given storage index.
“tahoe debug catalog-shares NODEDIRS..
” will look through one or more
storage nodes and locate every single share they contain. It produces a report
on stdout with one line per share, describing what kind of share it is, the
storage index, the size of the file is used for, etc. It may be useful to
concatenate these reports from all storage hosts and use it to look for
anomalies.
“tahoe debug dump-share SHAREFILE
” will take the name of a single share file
(as found by “tahoe find-shares
”) and print a summary of its contents to
stdout. This includes a list of leases, summaries of the hash tree, and
information from the UEB (URI Extension Block). For mutable file shares, it
will describe which version (seqnum and root-hash) is being stored in this
share.
“tahoe debug dump-cap CAP
” will take any Tahoe-LAFS URI and unpack it
into separate pieces. The most useful aspect of this command is to reveal the
storage index for any given URI. This can be used to locate the share files
that are holding the encoded+encrypted data for this file.
“tahoe debug corrupt-share SHAREFILE
” will flip a bit in the given
sharefile. This can be used to test the client-side verification/repair code.
Obviously, this command should not be used during normal operation.