Table of Contents
duplicity - Encrypted backup using rsync algorithm
duplicity
[options] source_directory target_url
duplicity [options] source_url target_directory
duplicity full [options] source_directory target_url
duplicity incremental
[options] source_directory target_url
duplicity restore [options] source_url
target_directory
duplicity verify [options] source_url target_directory
duplicity collection-status [options] target_url
duplicity list-current-files
[options] target_url
duplicity cleanup [options] [--force] target_url
duplicity
remove-older-than time [options] [--force] target_url
duplicity remove-all-but-n-full
count [options] [--force] target_url
duplicity remove-all-inc-of-but-n-full count
[options] [--force] target_url
Duplicity incrementally backs
up files and directory by encrypting tar-format volumes with GnuPG and uploading
them to a remote (or local) file server. Currently local, ftp, ssh/scp,
rsync, WebDAV, WebDAVs, Google Docs, HSi and Amazon S3 backends are available.
Because duplicity uses librsync, the incremental archives are space efficient
and only record the parts of files that have changed since the last backup.
Currently duplicity supports deleted files, full Unix permissions, directories,
symbolic links, fifos, etc., but not hard links.
If you are backing up the
root directory /, remember to --exclude /proc, or else duplicity will probably
crash on the weird stuff in there.
Here is an example of a backup,
using scp to back up /home/me to some_dir on the other.host machine:
duplicity
/home/me scp://uid@other.host/some_dir
If the above is run repeatedly, the
first will be a full backup, and subsequent ones will be incremental. To
force a full backup, use the full action:
duplicity full /home/me scp://uid@other.host/some_dir
Now suppose we accidentally delete /home/me and want to restore it the
way it was at the time of last backup:
duplicity scp://uid@other.host/some_dir
/home/me
Duplicity enters restore mode because the URL comes before the
local directory. If we wanted to restore just the file "Mail/article" in
/home/me as it was three days ago into /home/me/restored_file:
duplicity
-t 3D --file-to-restore Mail/article scp://uid@other.host/some_dir /home/me/restored_file
The following command compares the files we backed up, so see what has
changed since then:
duplicity verify scp://uid@other.host/some_dir /home/me
Finally, duplicity recognizes several include/exclude options. For instance,
the following will backup the root directory, but exclude /mnt, /tmp, and
/proc:
duplicity --exclude /mnt --exclude /tmp --exclude /proc / file:///usr/local/backup
Note that in this case the destination is the local directory /usr/local/backup.
The following will backup only the /home and /etc directories under root:
duplicity --include /home --include /etc --exclude ’**’ / file:///usr/local/backup
Duplicity can also access a repository via ftp. If a user name is given,
the environment variable FTP_PASSWORD is read to determine the password:
FTP_PASSWORD=mypassword duplicity /local/dir ftp://user@other.host/some_dir
- cleanup
- Delete the extraneous duplicity files on the given backend.
Non-duplicity files, or files in complete data sets will not be deleted.
This should only be necessary after a duplicity session fails or is aborted
prematurely. Note that --force will be needed to delete the files rather
than just list them.
- collection-status
- Summarize the status of the backup
repository by printing the chains and sets found, and the number of volumes
in each.
- full
- Indicate full backup. If this is set, perform full backup
even if signatures are available.
- incr
- If this is requested an incremental
backup will be performed. Duplicity will abort if old signatures cannot
be found. The default is to switch to full backup under these conditions.
- list-current-files
- Lists the files currently backed up in the archive. The
information will be extracted from the signature files, not the archive
data itself. Thus the whole archive does not have to be downloaded, but
on the other hand if the archive has been deleted or corrupted, this command
may not detect it.
- remove-older-than time
- Delete all backup sets older than
the given time. Old backup sets will not be deleted if backup sets newer
than time depend on them. See the TIME FORMATS section for more information.
Note, this action cannot be combined with backup or other actions, such
as cleanup. Note also that --force will be needed to delete the files rather
than just list them.
- remove-all-but-n-full count
- Delete all backups sets that
are older than the count:th last full backup (in other words, keep the
last count full backups and associated incremental sets). count must be
larger than zero. A value of 1 means that only the single most recent backup
chain will be kept. Note that --force will be needed to delete the files
rather than just list them.
- remove-all-inc-of-but-n-full count
- Delete incremental
sets of all backups sets that are older than the count:th last full backup
(in other words, keep only old full backups and not their increments). count
must be larger than zero. A value of 1 means that only the single most recent
backup chain will be kept intact. Note that --force will be needed to delete
the files rather than just list them.
- verify
- Enter verify mode instead
of restore. If the --file-to-restore option is given, restrict verify to that
file or directory. duplicity will exit with a non-zero error level if any
files are different. On verbosity level 4 or higher, log a message for
each file that has changed.
- --allow-source-mismatch
- Do not abort on
attempts to use the same archive dir or remote backend to back up different
directories. duplicity will tell you if you need this switch.
- --archive-dir
path
- The archive directory. NOTE: This option changed in 0.6.0. The archive
directory is now necessary in order to manage persistence for current and
future enhancements. As such, this option is now used only to change the
location of the archive directory. The archive directory should not be
deleted, or duplicity will have to recreate it from the remote repository
(which may require decrypting the backup contents).
When backing up or
restoring, this option specifies that the local archive directory is to
be created in path. If the archive directory is not specified, the default
will be to create the archive directory in ~/.cache/duplicity/.
The archive
directory can be shared between backups to multiple targets, because a
subdirectory of the archive dir is used for individual backups (see --name
).
The combination of archive directory and backup name must be unique
in order to separate the data of different backups.
The interaction between
the --archive-dir and the --name options allows for four possible combinations
for the location of the archive dir:
- 1.
- neither specified (default) ~/.cache/duplicity/
hash-of-url
- 2.
- --archive-dir=/arch, no --name /arch/
hash-of-url
- 3.
- no --archive-dir, --name=foo ~/.cache/duplicity/foo
- 4.
- --archive-dir=/arch, --name=foo /arch/foo
- --asynchronous-upload
- (EXPERIMENTAL) Perform file uploads asynchronously
in the background, with respect to volume creation. This means that duplicity
can upload a volume while, at the same time, preparing the next volume
for upload. The intended end-result is a faster backup, because the local
CPU and your bandwidth can be more consistently utilized. Use of this option
implies additional need for disk space in the temporary storage location;
rather than needing to store only one volume at a time, enough storage
space is required to store two volumes.
- --dry-run
- Calculate what would be
done, but do not perform any backend actions
- --encrypt-key key
- When backing
up, encrypt to the given public key, instead of using symmetric (traditional)
encryption. Can be specified multiple times.
- --encrypt-secret-keyring filename
- This option can only be used with --encrypt-key, and changes the path to the
secret keyring for the encrypt key to filename This keyring is not used
when creating a backup. If not specified, the default secret keyring is
used which is usually located at .gnupg/secring.gpg
- --encrypt-sign-key key
- Convenience
parameter. Same as --encrypt-key key --sign-key key.
- --exclude shell_pattern
- Exclude
the file or files matched by shell_pattern. If a directory is matched, then
files under that directory will also be matched. See the FILE SELECTION
section for more information.
- --exclude-device-files
- Exclude all device files.
This can be useful for security/permissions reasons or if rdiff-backup
is not handling device files correctly.
- --exclude-filelist filename
- Excludes
the files listed in filename. See the FILE SELECTION section for more information.
- --exclude-filelist-stdin
- Like --exclude-filelist, but the list of files will
be read from standard input. See the FILE SELECTION section for more information.
- --exclude-globbing-filelist filename
- Like --exclude-filelist but each line of
the filelist will be interpreted according to the same rules as --include
and --exclude.
- --exclude-if-present filename
- Exclude directories if filename
is present. This option needs to come before any other include or exclude
options.
- --exclude-other-filesystems
- Exclude files on file systems (identified
by device number) other than the file system the root of the source directory
is on.
- --exclude-regexp regexp
- Exclude files matching the given regexp. Unlike
the --exclude option, this option does not match files in a directory it
matches. See the FILE SELECTION section for more information.
- --extra-clean
- When cleaning up, be more aggressive about saving space. For example, this
may delete signature files for old backup chains. See the cleanup argument
for more information.
- --file-to-restore path
- This option may be given in restore
mode, causing only path to be restored instead of the entire contents of
the backup archive. path should be given relative to the root of the directory
backed up.
- --full-if-older-than time
- Perform a full backup if an incremental
backup is requested, but the latest full backup in the collection is older
than the given time. See the TIME FORMATS section for more information.
- --force
- Proceed even if data loss might result. Duplicity will let the user
know when this option is required.
- --ftp-passive
- Use passive (PASV) data connections.
The default is to use passive, but to fallback to regular if the passive
connection fails or times out.
- --ftp-regular
- Use regular (PORT) data connections.
- --gio
- Use the GIO backend and interpret any URLs as GIO would.
- --ignore-errors
- Try to ignore certain errors if they happen. This option is only intended
to allow the restoration of a backup in the face of certain problems that
would otherwise cause the backup to fail. It is not ever recommended to
use this option unless you have a situation where you are trying to restore
from backup and it is failing because of an issue which you want duplicity
to ignore. Even then, depending on the issue, this option may not have an
effect.
Please note that while ignored errors will be logged, there will
be no summary at the end of the operation to tell you what was ignored,
if anything. If this is used for emergency restoration of data, it is recommended
that you run the backup in such a way that you can revisit the backup log
(look for lines containing the string IGNORED_ERROR).
If you ever have
to use this option for reasons that are not understood or understood but
not your own responsibility, please contact duplicity maintainers. The need
to use this option under production circumstances would normally be considered
a bug.
- --imap-mailbox option
- Allows you to specify a different mailbox. The
default is "INBOX". Other languages may require a different mailbox than
the default.
- --gpg-options options
- Allows you to pass options to gpg encryption.
The options list should be of the form "opt1=parm1 opt2=parm2" where the
string is quoted and the only spaces allowed are between options.
- --include
shell_pattern
- Similar to --exclude but include matched files instead. Unlike
--exclude, this option will also match parent directories of matched files
(although not necessarily their contents). See the FILE SELECTION section
for more information.
- --include-filelist filename
- Like --exclude-filelist, but
include the listed files instead. See the FILE SELECTION section for more
information.
- --include-filelist-stdin
- Like --include-filelist, but read the list
of included files from standard input.
- --include-globbing-filelist filename
- Like --include-filelist but each line of the filelist will be interpreted
according to the same rules as --include and --exclude.
- --include-regexp regexp
- Include files matching the regular expression regexp. Only files explicitly
matched by regexp will be included by this option. See the FILE SELECTION
section for more information.
- --log-fd number
- Write specially-formatted versions
of output messages to the specified file descriptor. The format used is
designed to be easily consumable by other programs.
- --log-file filename
- Write
specially-formatted versions of output messages to the specified file. The
format used is designed to be easily consumable by other programs.
- --name
symbolicname
- Set the symbolic name of the backup being operated on. The
intent is to use a separate name for each logically distinct backup. For
example, someone may use "home_daily_s3" for the daily backup of a home
directory to Amazon S3. The structure of the name is up to the user, it
is only important that the names be distinct. The symbolic name is currently
only used to affect the expansion of --archive-dir , but may be used for additional
features in the future. Users running more than one distinct backup are
encouraged to use this option.
If not specified, the default value is a
hash of the backend URL.
- --no-encryption
- Do not use GnuPG to encrypt files
on remote system. Instead just write gzipped volumes.
- --no-print-statistics
- By default duplicity will print statistics about the current session after
a successful backup. This switch disables that behavior.
- --null-separator
- Use nulls (\0) instead of newlines (\n) as line separators, which may help
when dealing with filenames containing newlines. This affects the expected
format of the files specified by the --{include|exclude}-filelist[-stdin] switches
as well as the format of the directory statistics file.
- --numeric-owner
- On
restore always use the numeric uid/gid from the archive and not the archived
user/group names, which is the default behaviour. Recommended for restoring
from live cds which might have the users with identical names but different
uids/gids.
- --num-retries number
- Number of retries to make on errors before
giving up.
- --old-filenames
- Use the old filename format (incompatible with
Windows/Samba) rather than the new filename format.
- --rename orig new
- Treats
the path orig in the backup as if it were the path new. Can be passed multiple
times. An example:
duplicity restore --rename Documents/metal Music/metal
scp://uid@other.host/some_dir /home/me
- --rsync-options options
- Allows you
to pass options to the rsync backend. The options list should be of the
form "opt1=parm1 opt2=parm2" where the option string is quoted and the
only spaces allowed are between options. The option string will be passed
verbatim to rsync, after any internally generated option designating the
remote port to use. Here is a possibly useful example:
duplicity --rsync-options="--partial-dir=.rsync-partial"
/home/me scp://uid@other.host/some_dir
- --s3-european-buckets
- When using the
Amazon S3 backend, create buckets in Europe instead of the default (requires
--s3-use-new-style ). Also see the EUROPEAN S3 BUCKETS section.
- --s3-unencrypted-connection
- Don’t use SSL for connections to S3.
This may be much faster, at some cost
to confidentiality.
With this option, anyone who can observe traffic between
your computer and S3 will be able to tell: that you are using Duplicity,
the name of the bucket, your AWS Access Key ID, the increment dates and
the amount of data in each increment.
This option affects only the connection,
not the GPG encryption of the backup increment files. Unless that is disabled,
an observer will not be able to see the file names or contents.
- --s3-use-new-style
- When operating on Amazon S3 buckets, use new-style subdomain bucket addressing.
This is now the preferred method to access Amazon S3, but is not backwards
compatible if your bucket name contains upper-case characters or other characters
that are not valid in a hostname.
- --scp-command command
- This option only matters
when using the ssh/scp backend. The command will be used instead of scp
to send or receive files. The default command is "scp". To list and delete
existing files, the sftp command is used. See --ssh-options and --sftp-command.
- --sftp-command command
- This option only matters when using the ssh/scp backend.
The command will be used instead of sftp for listing and deleting files.
The default is "sftp". File transfers are done using the sftp command. See
--ssh-options, --use-scp, and --scp-command.
- --sign-key key
- This option can be used
when backing up, restoring or verifying. When backing up, all backup files
will be signed with keyid key. When restoring, duplicity will signal an
error if any remote file is not signed with the given keyid. key should
be an 8 character hex string, like AA0E73D2. Should be specified only once
because currently only one signing key is supported. Last entry overrides
all other entries.
see also A NOTE ON SYMMETRIC ENCRYPTION AND SIGNING
- --ssh-askpass
- Tells the
ssh/scp backend to use FTP_PASSWORD from the environment, or, if that is
not present, to prompt the user for the remote system password.
- --ssh-options
options
- Allows you to pass options to the ssh/scp/sftp backend. The options
list should be of the form "opt1=parm1 opt2=parm2" where the option string
is quoted and the only spaces allowed are between options. The option string
will be passed verbatim to both scp and sftp, whose command line syntax
differs slightly: options passed with --ssh-options should therefore be given
in the long option format described in ssh_config(5)
, like in this example:
duplicity --ssh-options="-oProtocol=2 -oIdentityFile=/my/backup/id" /home/me
scp://uid@other.host/some_dir
- --short-filenames
- If this option is specified,
the names of the files duplicity writes will be shorter (about 30 chars)
but less understandable. This may be useful when backing up to MacOS or
another OS or FS that doesn’t support long filenames.
- --tempdir directory
- Use this existing directory for duplicity temporary files instead of the
system default, which is usually the /tmp directory. This option supersedes
any environment variable.
- -ttime, --time time, --restore-time time
- Specify the
time from which to restore or list files.
- --time-separator char
- Use char as
the time separator in filenames instead of colon (":").
- --timeout seconds
- Use seconds as the socket timeout value if duplicity begins to timeout
during network operations. The default is 30 seconds.
- --use-agent
- If this
option is specified, then --use-agent is passed to the GnuPG encryption process
and it will try to connect to gpg-agent before it asks for a passphrase
for --encrypt-key or --sign-key if needed.
Note: GnuPG 2 and newer ignore this option and will always use a running
gpg-agent if no passphrase was delivered.
- --use-scp
- If this option is specified,
then the ssh backend will use scp rather than sftp for the get and put
backend operations. The default is to use sftp for all operations. With
this option, duplicity will use sftp for list and delete operations, and
scp for put and get operations
- --verbosity level, -vlevel
- Specify output
verbosity level (log level). Named levels and corresponding values are 0
Error, 2 Warning, 4 Notice (default), 8 Info, 9 Debug (noisiest).
level may also be
a character: e, w, n, i, d
a word: error, warning, notice, info, debug
The options -v4, -vn and -vnotice
are functionally equivalent, as are the mixed/-vNotice and -vNOTICE.
- --version
- Print duplicity’s version and quit.
- --volsize number
- Change the volume size
to number Mb. Default is 25Mb.
- TMPDIR, TEMP, TMP
- In
decreasing order of importance, specifies the directory to use for temporary
files (inherited from Python’s tempfile module).
- FTP_PASSWORD
- Supported by
most backends which are password capable. More secure than setting it in
the backend url (which might be readable in the operating systems process
listing to other users on the same machine).
- PASSPHRASE
- This passphrase
is passed to GnuPG. If this is not set, the user will be prompted for the
passphrase.
- SIGN_PASSPHRASE
- The passphrase to be used for --sign-key , if SIGN_PASSPHRASE
is not set but PASSPHRASE is set, the latter will be used. Otherwise, if
no passphrase is available, the user will be prompted for it.
Duplicity
tries to maintain a standard URL format as much as possible. The generic
format for a URL is:
scheme://user[:password]@host[:port]/[/]path
It is
not recommended to expose the password on the command line since it could
be revealed to anyone with permissions to do process listings, however,
it is permitted. Consider setting the environment variable FTP_PASSWORD
instead, which is supported by most, but not all backends. Regardless of
its name it can be used with other backends.
In protocols that support it,
the path may be preceded by a single slash, ’/path’, to represent a relative
path to the target home directory, or preceded by a double slash, ’//path’,
to represent an absolute filesystem path.
Formats of each of the URL schemes
follow:
cf+http://container_name
file:///some_dir
ftp[s]://user[:password]@other.host[:port]/some_dir
hsi://user[:password]@other.host/some_dir
imap[s]://user[:password]@host.com[/from_address_prefix]
see also A NOTE ON IMAP
using rsync daemon
rsync://user[:password]@host.com[:port]::[/]module/some_dir
using rsync
over ssh (only key auth)
rsync://user@host.com[:port]/relative_path
rsync://user@host.com[:port]//absolute_path
s3://host/bucket_name[/prefix]
s3+http://bucket_name[/prefix]
see also A NOTE ON EUROPEAN S3 BUCKETS
Ubuntu One
u1://host/volume_path
u1+http://volume_path
see also A NOTE ON UBUNTU ONE
ssh protocols
scp://.. or sftp://.. are synonymous for
ssh://user[:password]@other.host[:port]/[/]some_dir
see also A NOTE ON SSH/SCP PROTOCOLS and --use-scp
tahoe://alias/directory
webdav[s]://user[:password]@other.host/some_dir
gdocs://user[:password]@other.host/some_dir
duplicity uses time strings in two places. Firstly, many
of the files duplicity creates will have the time in their filenames in
the w3 datetime format as described in a w3 note at http://www.w3.org/TR/NOTE-datetime.
Basically they look like "2001-07-15T04:09:38-07:00", which means what it
looks like. The "-07:00" section means the time zone is 7 hours behind UTC.
Secondly, the -t, --time, and --restore-time options take a time string, which
can be given in any of several formats:
- 1.
- the string "now" (refers to the
current time)
- 2.
- a sequences of digits, like "123456890" (indicating the
time in seconds after the epoch)
- 3.
- A string like "2002-01-25T07:00:00+02:00"
in datetime format
- 4.
- An interval, which is a number followed by one of the
characters s, m, h, D, W, M, or Y (indicating seconds, minutes, hours,
days, weeks, months, or years respectively), or a series of such pairs.
In this case the string refers to the time that preceded the current time
by the length of the interval. For instance, "1h78m" indicates the time
that was one hour and 78 minutes ago. The calendar here is unsophisticated:
a month is always 30 days, a year is always 365 days, and a day is always
86400 seconds.
- 5.
- A date format of the form YYYY/MM/DD, YYYY-MM-DD, MM/DD/YYYY,
or MM-DD-YYYY, which indicates midnight on the day in question, relative
to the current time zone settings. For instance, "2002/3/5", "03-05-2002",
and "2002-3-05" all mean March 5th, 2002.
duplicity accepts
the same file selection options rdiff-backup does, including --exclude, --exclude-filelist-stdin,
etc.
When duplicity is run, it searches through the given source directory
and backs up all the files specified by the file selection system. The
file selection system comprises a number of file selection conditions,
which are set using one of the following command line options: --exclude,
--exclude-device-files, --exclude-filelist, --exclude-filelist-stdin, --exclude-globbing-filelist,
--exclude-regexp, --include, --include-filelist, --include-filelist-stdin, --include-globbing-filelist,
and --include-regexp. Each file selection condition either matches or doesn’t
match a given file. A given file is excluded by the file selection system
exactly when the first matching file selection condition specifies that
the file be excluded; otherwise the file is included.
For instance,
duplicity
--include /usr --exclude /usr /usr scp://user@host/backup
is exactly the same
as
duplicity /usr scp://user@host/backup
because the include and exclude
directives match exactly the same files, and the --include comes first, giving
it precedence. Similarly,
duplicity --include /usr/local/bin --exclude /usr/local
/usr scp://user@host/backup
would backup the /usr/local/bin directory (and
its contents), but not /usr/local/doc.
The include, exclude, include-globbing-filelist,
and exclude-globbing-filelist options accept extended shell globbing patterns.
These patterns can contain the special patterns *, **, ?, and [...]. As in
a normal shell, * can be expanded to any string of characters not containing
"/", ? expands to any character except "/", and [...] expands to a single
character of those characters specified (ranges are acceptable). The new
special pattern, **, expands to any string of characters whether or not
it contains "/". Furthermore, if the pattern starts with "ignorecase:" (case
insensitive), then this prefix will be removed and any character in the
string can be replaced with an upper- or lowercase version of itself.
Remember
that you may need to quote these characters when typing them into a shell,
so the shell does not interpret the globbing patterns before duplicity
sees them.
The --exclude pattern option matches a file iff:
.- pattern can
be expanded into the file’s filename, or
.- the file is inside a directory
matched by the option.
Conversely, --include pattern matches a file iff:
.- pattern can be expanded into the file’s filename,
.- the file is inside a
directory matched by the option, or
.- the file is a directory which contains
a file matched by the option.
For example,
--exclude /usr/local
matches /usr/local,
/usr/local/lib, and /usr/local/lib/netscape. It is the same as --exclude
/usr/local --exclude ’/usr/local/**’.
--include /usr/local
specifies that /usr,
/usr/local, /usr/local/lib, and /usr/local/lib/netscape (but not /usr/doc)
all be backed up. Thus you don’t have to worry about including parent directories
to make sure that included subdirectories have somewhere to go. Finally,
--include ignorecase:’/usr/[a-z0-9]foo/*/**.py’
would match a file like /usR/5fOO/hello/there/world.py.
If it did match anything, it would also match /usr. If there is no existing
file that the given pattern can be expanded into, the option will not match
/usr.
The --include-filelist, --exclude-filelist, --include-filelist-stdin, and --exclude-filelist-stdin
options also introduce file selection conditions. They direct duplicity
to read in a file, each line of which is a file specification, and to include
or exclude the matching files. Lines are separated by newlines or nulls,
depending on whether the --null-separator switch was given. Each line in a
filelist is interpreted similarly to the way extended shell patterns are,
with a few exceptions:
.- Globbing patterns like *, **, ?, and [...] are not
expanded.
.- Include patterns do not match files in a directory that is included.
So /usr/local in an include file will not match /usr/local/doc.
.- Lines starting
with "+ " are interpreted as include directives, even if found in a filelist
referenced by --exclude-filelist. Similarly, lines starting with "- " exclude
files even if they are found within an include filelist.
For example, if
file "list.txt" contains the lines:
/usr/local
- /usr/local/doc
/usr/local/bin
+ /var
- /var
then "--include-filelist list.txt" would include /usr, /usr/local,
and /usr/local/bin. It would exclude /usr/local/doc, /usr/local/doc/python,
etc. It neither excludes nor includes /usr/local/man, leaving the fate
of this directory to the next specification condition. Finally, it is undefined
what happens with /var. A single file list should not contain conflicting
file specifications.
The --include-globbing-filelist and --exclude-globbing-filelist
options also specify filelists, but each line in the filelist will be interpreted
as a globbing pattern the way --include and --exclude options are interpreted
(although "+ " and "- " prefixing is still allowed). For instance, if the
file "globbing-list.txt" contains the lines:
dir/foo
+ dir/bar
- **
Then
"--include-globbing-filelist globbing-list.txt" would be exactly the same as
specifying "--include dir/foo --include dir/bar --exclude **" on the command
line.
Finally, the --include-regexp and --exclude-regexp allow files to be included
and excluded if their filenames match a python regular expression. Regular
expression syntax is too complicated to explain here, but is covered in
Python’s library reference. Unlike the --include and --exclude options, the
regular expression options don’t match files containing or contained in
matched files. So for instance
--include ’[0-9]{7}(?!foo)’
matches any files
whose full pathnames contain 7 consecutive digits which aren’t followed
by ’foo’. However, it wouldn’t match /home even if /home/ben/1234567 existed.
Amazon S3 provides the ability to choose
the location of a bucket upon its creation. The purpose is to enable the
user to choose a location which is better located network topologically
relative to the user, because it may allow for faster data transfers.
duplicity
will create a new bucket the first time a bucket access is attempted. At
this point, the bucket will be created in Europe if --s3-european-buckets was
given. For reasons having to do with how the Amazon S3 service works, this
also requires the use of the --s3-use-new-style option. This option turns on
subdomain based bucket addressing in S3. The details are beyond the scope
of this man page, but it is important to know that your bucket must not
contain upper case letters or any other characters that are not valid parts
of a hostname. Consequently, for reasons of backwards compatibility, use
of subdomain based bucket addressing is not enabled by default.
Note that
you will need to use --s3-use-new-style for all operations on European buckets;
not just upon initial creation.
You only need to use --s3-european-buckets upon
initial creation, but you may may use it at all times for consistency.
Further
note that when creating a new European bucket, it can take a while before
the bucket is fully accessible. At the time of this writing it is unclear
to what extent this is an expected feature of Amazon S3, but in practice
you may experience timeouts, socket errors or HTTP errors when trying to
upload files to your newly created bucket. Give it a few minutes and the
bucket should function normally.
An IMAP account can be used
as a target for the upload. The userid may be specified and the password
will be requested.
The from_address_prefix may be specified (and probably
should be). The text will be used as the "From" address in the IMAP server.
Then on a restore (or list) command the from_address_prefix will distinguish
between different backups.
Duplicity specifies
two protocol names for the same protocol. This is a known and user-confusing
issue. Both use the same protocol suite, namely ssh through its’ utility
routines scp and sftp. Older versions of duplicity used scp for get and
put operations and sftp for list and delete operations. The current version
uses sftp for all four supported operations, unless the --use-scp option is
used to revert to old behavior. The change was made to all-sftp in order
to allow the remote system to chroot the backup, thus providing better
security.
Connecting to Ubuntu One requires that you
be running duplicity inside of an X session so that you can be prompted
for your credentials if necessary by the Ubuntu One session daemon.
See
https://one.ubuntu.com/
for more information about Ubuntu One.
Signing and symmetrically encrypt at the
same time with the gpg binary on the command line, as used within duplicity,
is a specifically challenging issue. Tests showed that the following combinations
proved working.
1. Setup gpg-agent properly. Use the option --use-agent and enter
both passphrases (symmetric and sign key) in the gpg-agent’s dialog.
2. Use
a PASSPHRASE for symmetric encryption of your choice but the signing key
has an empty passphrase.
3. The used PASSPHRASE for symmetric encryption
and the passphrase of the signing key are identical.
Hard
links currently unsupported (they will be treated as non-linked regular
files).
Bad signatures will be treated as empty instead of logging appropriate
error message.
This section describes duplicity’s
basic operation and the format of its data files. It should not necessary
to read this section to use duplicity.
The files used by duplicity to store
backup data are tarfiles in GNU tar format. They can be produced independently
by rdiffdir(1)
. For incremental backups, new files are saved normally in
the tarfile. But when a file changes, instead of storing a complete copy
of the file, only a diff is stored, as generated by rdiff(1)
. If a file
is deleted, a 0 length file is stored in the tar. It is possible to restore
a duplicity archive "manually" by using tar and then cp, rdiff, and rm
as necessary. These duplicity archives have the extension difftar.
Both
full and incremental backup sets have the same format. In effect, a full
backup set is an incremental one generated from an empty signature (see
below). The files in full backup sets will start with duplicity-full while
the incremental sets start with duplicity-inc. When restoring, duplicity
applies patches in order, so deleting, for instance, a full backup set
may make related incremental backup sets unusable.
In order to determine
which files have been deleted, and to calculate diffs for changed files,
duplicity needs to process information about previous sessions. It stores
this information in the form of tarfiles where each entry’s data contains
the signature (as produced by rdiff) of the file instead of the file’s contents.
These signature sets have the extension sigtar.
Signature files are not
required to restore a backup set, but without an up-to-date signature, duplicity
cannot append an incremental backup to an existing archive.
To save bandwidth,
duplicity generates full signature sets and incremental signature sets.
A full signature set is generated for each full backup, and an incremental
one for each incremental backup. These start with duplicity-full-signatures
and duplicity-new-signatures respectively. These signatures will be stored
both locally and remotely. The remote signatures will be encrypted if encryption
is enabled. The local signatures will not be encrypted and stored in the
archive dir (see --archive-dir ).
Original Author - Ben Escoto <bescoto@stanford.edu>
Current Maintainer - Kenneth Loafman <kenneth@loafman.com>
rdiffdir(1)
,
python(1)
, rdiff(1)
, rdiff-backup(1)
.
Table of Contents