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bup-ftp(1) [debian man page]

bup-ftp(1)						      General Commands Manual							bup-ftp(1)

bup-ftp - ftp-like client for navigating bup repositories SYNOPSIS
bup ftp is a command-line tool for navigating bup repositories. It has commands similar to the Unix ftp(1) command. The file hierarchy is the same as that shown by bup-fuse(1) and bup-ls(1). Note: if your system has the python-readline library installed, you can use the <tab> key to complete filenames while navigating your backup data. This will save you a lot of typing. COMMANDS
The following commands are available inside bup ftp: ls [-s] [-a] [path] print the contents of a directory. If no path argument is given, the current directory's contents are listed. If -a is given, also include hidden files (files which start with a . character). If -s is given, each file is displayed with its hash from the bup ar- chive to its left. cd dirname change to a different working directory pwd print the path of the current working directory cat filenames... print the contents of one or more files to stdout get filename localname download the contents of filename and save it to disk as localname. If localname is omitted, uses filename as the local name. mget filenames... download the contents of the given filenames and stores them to disk under the same names. The filenames may contain Unix filename globs (*, ?, etc.) help print a list of available commands quit exit the bup ftp client EXAMPLE
$ bup ftp bup> ls mybackup/ yourbackup/ bup> cd mybackup/ bup> ls 2010-02-05-185507@ 2010-02-05-185508@ latest@ bup> cd latest/ bup> ls (...etc...) bup> get myfile Saving 'myfile' bup> quit SEE ALSO
bup-fuse(1), bup-ls(1), bup-save(1), bup-restore(1) BUP
Part of the bup(1) suite. AUTHORS
Avery Pennarun <>. Bup unknown- bup-ftp(1)

Check Out this Related Man Page

bup-margin(1)						      General Commands Manual						     bup-margin(1)

bup-margin - figure out your deduplication safety margin SYNOPSIS
bup margin [options...] DESCRIPTION
bup margin iterates through all objects in your bup repository, calculating the largest number of prefix bits shared between any two entries. This number, n, identifies the longest subset of SHA-1 you could use and still encounter a collision between your object ids. For example, one system that was tested had a collection of 11 million objects (70 GB), and bup margin returned 45. That means a 46-bit hash would be sufficient to avoid all collisions among that set of objects; each object in that repository could be uniquely identified by its first 46 bits. The number of bits needed seems to increase by about 1 or 2 for every doubling of the number of objects. Since SHA-1 hashes have 160 bits, that leaves 115 bits of margin. Of course, because SHA-1 hashes are essentially random, it's theoretically possible to use many more bits with far fewer objects. If you're paranoid about the possibility of SHA-1 collisions, you can monitor your repository by running bup margin occasionally to see if you're getting dangerously close to 160 bits. OPTIONS
--predict Guess the offset into each index file where a particular object will appear, and report the maximum deviation of the correct answer from the guess. This is potentially useful for tuning an interpolation search algorithm. --ignore-midx don't use .midx files, use only .idx files. This is only really useful when used with --predict. EXAMPLE
$ bup margin Reading indexes: 100.00% (1612581/1612581), done. 40 40 matching prefix bits 1.94 bits per doubling 120 bits (61.86 doublings) remaining 4.19338e+18 times larger is possible Everyone on earth could have 625878182 data sets like yours, all in one repository, and we would expect 1 object collision. $ bup margin --predict PackIdxList: using 1 index. Reading indexes: 100.00% (1612581/1612581), done. 915 of 1612581 (0.057%) SEE ALSO
bup-midx(1), bup-save(1) BUP
Part of the bup(1) suite. AUTHORS
Avery Pennarun <>. Bup unknown- bup-margin(1)

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