From 14d43f1fcf4904f401a0cb38efb921b29a6652b1 Mon Sep 17 00:00:00 2001 From: David Dykstra Date: Wed, 18 Nov 1998 17:36:36 +0000 Subject: [PATCH] Minor documentation patches, due mostly to Jason Henry Parker --- README | 2 +- options.c | 4 +-- rsync.yo | 89 ++++++++++++++++++++++++++----------------------- rsyncd.conf.yo | 10 +++--- tech_report.tex | 22 ++++++------ 5 files changed, 66 insertions(+), 61 deletions(-) diff --git a/README b/README index b49875cb..20660579 100644 --- a/README +++ b/README @@ -66,7 +66,7 @@ SETUP ----- Rsync uses rsh or ssh for communication. It does not need to be setuid -and requires no special privilages for installation. It does not +and requires no special privileges for installation. It does not require a inetd entry or a daemon. You must, however, have a working rsh or ssh system. Using ssh is recommended for its security features. diff --git a/options.c b/options.c index 0896152b..58f0f3f0 100644 --- a/options.c +++ b/options.c @@ -86,9 +86,9 @@ void usage(int F) rprintf(F,"Usage: rsync [OPTION]... SRC [USER@]HOST:DEST\n"); rprintf(F," or rsync [OPTION]... [USER@]HOST:SRC DEST\n"); rprintf(F," or rsync [OPTION]... SRC DEST\n"); - rprintf(F," or rsync [OPTION]... [USER@]HOST::SRC DEST\n"); + rprintf(F," or rsync [OPTION]... [USER@]HOST::SRC [DEST]\n"); rprintf(F," or rsync [OPTION]... SRC [USER@]HOST::DEST\n"); - rprintf(F," or rsync [OPTION]... rsync://[USER@]HOST[:PORT]/SRC DEST\n"); + rprintf(F," or rsync [OPTION]... rsync://[USER@]HOST[:PORT]/SRC [DEST]\n"); rprintf(F,"\nOptions\n"); rprintf(F," -v, --verbose increase verbosity\n"); rprintf(F," -c, --checksum always checksum\n"); diff --git a/rsync.yo b/rsync.yo index 1074c24d..f5276583 100644 --- a/rsync.yo +++ b/rsync.yo @@ -70,8 +70,8 @@ itemize( local destination. ) -Note that in all cases at least one of the source and destination -paths must be local. +Note that in all cases (other than listing) at least one of the source +and destination paths must be local. manpagesection(SETUP) @@ -81,7 +81,7 @@ Once installed you can use rsync to any machine that you can use rsh to. rsync uses rsh for its communications, unless both the source and destination are local. -You can also specify a alternative to rsh, by either using the -e +You can also specify an alternative to rsh, by either using the -e command line option, or by setting the RSYNC_RSH environment variable. One common substitute is to use ssh, which offers a high degree of @@ -107,18 +107,18 @@ differences. See the tech report for details. quote(rsync -avz foo:src/bar /data/tmp) -recursively transfer all files from the directory src/bar on the +this would recursively transfer all files from the directory src/bar on the machine foo into the /data/tmp/bar directory on the local machine. The files are transferred in "archive" mode, which ensures that symbolic links, devices, attributes, permissions, ownerships etc are preserved -in the transfer. Additionally compression will be used to reduce the +in the transfer. Additionally, compression will be used to reduce the size of data portions of the transfer. quote(rsync -avz foo:src/bar/ /data/tmp) -With a trailing slash on the source this behavior changes to transfer +a trailing slash on the source changes this behavior to transfer all files from the directory src/bar on the machine foo into the -/data/tmp/. With a trailing / on a source name it means "copy the +/data/tmp/. A trailing / on a source name means "copy the contents of this directory". Without a trailing slash it means "copy the directory". This difference becomes particularly important when using the --delete option. @@ -127,6 +127,11 @@ You can also use rsync in local-only mode, where both the source and destination don't have a ':' in the name. In this case it behaves like an improved copy command. +quote(rsync somehost.mydomain.com::) + +this would list all the anonymous rsync modules available on the host +somehost.mydomain.com. (See the following section for more details.) + manpagesection(CONNECTING TO AN RSYNC SERVER) @@ -134,7 +139,7 @@ It is also possible to use rsync without using rsh or ssh as the transport. In this case you will connect to a remote rsync server running on TCP port 873. -Using rsync in this was is the same as using it with rsh or ssh except +Using rsync in this way is the same as using it with rsh or ssh except that: itemize( @@ -142,13 +147,13 @@ itemize( separate the hostname from the path. it() the remote server may print a message of the day when you - connect + connect. it() if you specify no path name on the remote server then the list of accessible paths on the server will be shown. - + it() if you specify no local destination then a listing of the - specified files on the remote server is provided + specified files on the remote server is provided. ) Some paths on the remote server may require authentication. If so then @@ -166,8 +171,8 @@ manpagesection(EXAMPLES) Here are some examples of how I use rsync. -To backup my wife's home directory, which consists of large MS word -files and mail folders I use a cron job that runs +To backup my wife's home directory, which consists of large MS Word +files and mail folders, I use a cron job that runs quote(rsync -Cavz . arvidsjaur:backup) @@ -198,16 +203,16 @@ this is launched from cron every few hours. manpagesection(OPTIONS SUMMARY) -Here is a short summary of the options avalable in rsync. Please refer +Here is a short summary of the options available in rsync. Please refer to the detailed description below for a complete description. verb( Usage: rsync [OPTION]... SRC [USER@]HOST:DEST or rsync [OPTION]... [USER@]HOST:SRC DEST or rsync [OPTION]... SRC DEST - or rsync [OPTION]... [USER@]HOST::SRC DEST + or rsync [OPTION]... [USER@]HOST::SRC [DEST] or rsync [OPTION]... SRC [USER@]HOST::DEST - or rsync [OPTION]... rsync://[USER@]HOST[:PORT]/SRC DEST + or rsync [OPTION]... rsync://[USER@]HOST[:PORT]/SRC [DEST] Options -v, --verbose increase verbosity @@ -262,7 +267,7 @@ manpageoptions() rsync uses the GNU long options package. Many of the command line options have two variants, one short and one long. These are shown -below separated by commas. Some options only have a long variant. +below, separated by commas. Some options only have a long variant. startdit() dit(bf(-h, --help)) Print a short help page describing the options @@ -271,12 +276,12 @@ available in rsync dit(bf(--version)) print the rsync version number and exit dit(bf(-v, --verbose)) This option increases the amount of information you -are given during the transfer. By default rsync works silently. A +are given during the transfer. By default, rsync works silently. A single -v will give you information about what files are being transferred and a brief summary at the end. Two -v flags will give you information on what files are being skipped and slightly more information at the end. More than two -v flags should only be used if -you are debugging rsync +you are debugging rsync. dit(bf(-I, --ignore-times)) Normally rsync will skip any files that are already the same length and have the same time-stamp. This option turns @@ -289,18 +294,18 @@ which already exist and have the same checksum and size on the receiver are skipped. This option can be quite slow. dit(bf(-a, --archive)) This is equivalent to -rlptDg. It is a quick way -of saying I want recursion and want to preserve everything. +of saying you want recursion and want to preserve everything. Note: if the user launching rsync is root then the -o option (preserve uid) is also implied. -dit(bf(-r, --recursive)) This tells rsync to copy directories recursively +dit(bf(-r, --recursive)) This tells rsync to copy directories recursively. dit(bf(-R, --relative)) Use relative paths. This means that the full path names specified on the command line are sent to the server rather than just the last parts of the filenames. This is particularly useful when -you want to sent several different directories at the same time. For -example if you used the command +you want to send several different directories at the same time. For +example, if you used the command verb(rsync foo/bar/foo.c remote:/tmp/) @@ -322,7 +327,7 @@ file. dit(bf(-l, --links)) This tells rsync to recreate symbolic links on the remote system to be the same as the local system. Without this -option all symbolic links are skipped. +option, all symbolic links are skipped. dit(bf(-L, --copy-links)) This tells rsync to treat symbolic links just like ordinary files. @@ -330,7 +335,7 @@ like ordinary files. dit(bf(--safe-links)) This tells rsync to ignore any symbolic links which point outside the destination tree. All absolute symlinks are also ignored. Using this option in conjunction with --relative may -give unexpecetd results. +give unexpected results. dit(bf(-H, --hard-links)) This tells rsync to recreate hard links on the remote system to be the same as the local system. Without this @@ -345,7 +350,7 @@ dit(bf(-W, --whole-file)) With this option the incremental rsync algorithm is not used and the whole file is sent as-is instead. This may be useful when using rsync with a local machine. -dit(bf(--partial)) By default rsync will delete any partially +dit(bf(--partial)) By default, rsync will delete any partially transferred file if the transfer is interrupted. In some circumstances it is more desirable to keep partially transferred files. Using the --partial option tells rsync to keep the partial file which should @@ -358,7 +363,7 @@ dit(bf(-o, --owner)) This option causes rsync to update the remote owner of the file to be the same as the local owner. This is only available to the super-user. Note that if the source system is a daemon using chroot, the --numeric-ids option is implied because the source system cannot get -access to the user names. +access to the usernames. dit(bf(-g, --group)) This option causes rsync to update the remote group of the file to be the same as the local group. Note that if the source @@ -428,14 +433,14 @@ the rsync algorithm. See the technical report for details. dit(bf(-e, --rsh COMMAND)) This option allows you to choose an alternative remote shell program to use for communication between the local and -remote copies of rsync. By default rsync will use rsh, but you may +remote copies of rsync. By default, rsync will use rsh, but you may like to instead use ssh because of its high security. You can also choose the remote shell program using the RSYNC_RSH environment variable. dit(bf(--rsync-path PATH)) Use this to specify the path to the copy of -rsync on the remote machine. Useful when its not in your path. +rsync on the remote machine. Useful when it's not in your path. dit(bf(--exclude pattern)) This option allows you to selectively exclude certain files from the list of files to be transferred. This is most @@ -444,7 +449,7 @@ useful in combination with a recursive transfer. You may use as many --exclude options on the command line as you like to build up the list of files to exclude. -See the section of exclude patterns for information on the syntax of +See the section on exclude patterns for information on the syntax of this option. dit(bf(--exclude-from FILE)) This option is similar to the --exclude @@ -509,7 +514,7 @@ dit(bf(--compare-dest DIR)) This option instructs rsync to use DIR as an additional directory to compare destination files against when doing transfers. This is useful for doing transfers to a new destination while leaving existing files intact, and then doing a flash-cutover when all -files have been successfully transfered (for example by moving directories +files have been successfully transferred (for example by moving directories around and removing the old directory, although this requires also doing the transfer with -I to avoid skipping files that haven't changed). This option increases the usefulness of --partial because partially transferred @@ -533,7 +538,7 @@ at both ends. By default rsync will use the user name and group name to determine what ownership to give files. The special uid 0 and the special group -0 and never mapped via user/group names even if the --numeric-ids +0 are never mapped via user/group names even if the --numeric-ids option is not specified. If the source system is a daemon using chroot, or if a user or group name @@ -557,10 +562,10 @@ the default /etc/rsyncd.conf. This is only relevant when --daemon is specified. dit(bf(--port PORT)) This specifies an alternate TCP port number to use -rather than the default port 873. +rather than the default port 873. dit(bf(--log-format=FORMAT)) This allows you to specify exactly what the -rsync client logs to stdout on a per file basis. The log format is +rsync client logs to stdout on a per-file basis. The log format is specified using the same format conventions as the log format option in rsyncd.conf. @@ -578,17 +583,17 @@ enddit() manpagesection(EXCLUDE PATTERNS) The exclude and include patterns specified to rsync allow for flexible -selection of what files to transfer and what files to skip. +selection of which files to transfer and which files to skip. -rsync build a ordered list of include/exclude options as specified on -the command line. When a filename is encountered rsync then checks the +rsync builds a ordered list of include/exclude options as specified on +the command line. When a filename is encountered, rsync checks the name against each exclude/include pattern in turn. The first matching pattern is acted on. If it is an exclude pattern than that file is skipped. If it is an include pattern then that filename is not skipped. If no matching include/exclude pattern is found then the filename is not skipped. -The patterns themselves can take several forms. The rules are: +The patterns can take several forms. The rules are: itemize( it() if the pattern starts with a / then it is matched against the @@ -637,13 +642,13 @@ itemize( manpagesection(DIAGNOSTICS) -rsync occasinally produces error messages that may seem a little +rsync occasionally produces error messages that may seem a little cryptic. The one that seems to cause the most confusion is "protocol version mismatch - is your shell clean?". This message is usually caused by your startup scripts or remote shell facility producing unwanted garbage on the stream that rsync is using -for its transport. The way ot diagnose this problem is to run your +for its transport. The way to diagnose this problem is to run your remote shell like this: verb( @@ -654,7 +659,7 @@ then look at out.dat. If everything is working correctly then out.dat should be a zero length file. You you are getting the above error from rsync then you will probably find that out.dat contains some text or data. Look at the contents and try to work out what is producing -it. The most common cause is incorrectly configued shell startup +it. The most common cause is incorrectly configured shell startup scripts (such as .cshrc or .profile) that contain output statements for non-interactive logins. @@ -678,7 +683,7 @@ password to a shell transport such as ssh. dit(bf(USER) or bf(LOGNAME)) The USER or LOGNAME environment variables are used to determine the default username sent to a rsync server. -dit(bf(HOME)) The HOME environment variable is used to find the users +dit(bf(HOME)) The HOME environment variable is used to find the user's default .cvsignore file. enddit() diff --git a/rsyncd.conf.yo b/rsyncd.conf.yo index 325e5dd9..a6a6b72e 100644 --- a/rsyncd.conf.yo +++ b/rsyncd.conf.yo @@ -46,7 +46,7 @@ manpagesection(LAUNCHING THE RSYNC DAEMON) The rsync daemon is launched by specifying the --daemon option to rsync. The daemon must run with root privileges. -You can launch it either via inetd or as a standalone daemon. If run +You can launch it either via inetd or as a stand-alone daemon. If run as a daemon then just run the command "rsync --daemon" from a suitable startup script. @@ -248,7 +248,7 @@ The default is no "hosts deny" option, which means all hosts can connect. dit(bf(transfer logging)) The "transfer logging" option enables per-file logging of downloads and uploads in a format somewhat similar to that -used by ftp daemons. If you want to customise the log formats look at +used by ftp daemons. If you want to customize the log formats look at the log format option. dit(bf(log format)) The "log format" option allows you to specify the @@ -276,11 +276,11 @@ itemize( The default log format is "%o %h [%a] %m (%u) %f %l" -A perl script called rsyncstats to summarise this format is included +A perl script called rsyncstats to summarize this format is included in the rsync source code distribution. dit(bf(timeout)) The "timeout" option allows you to override the -clients choice for IO timoeut for this module. Using this option you +clients choice for IO timeout for this module. Using this option you can ensure that rsync won't wait on a dead client forever. The timeout is specified in seconds. A value of zero means no timeout and is the default. A good choice for anonymous rsync servers may be 600 (giving @@ -293,7 +293,7 @@ manpagesection(AUTHENTICATION STRENGTH) The authentication protocol used in rsync is a 128 bit MD4 based challenge response system. Although I believe that no one has ever demonstrated a brute-force break of this sort of system you should -realise that this is not a "military strength" authentication system. +realize that this is not a "military strength" authentication system. It should be good enough for most purposes but if you want really top quality security then I recommend that you run rsync over ssh. diff --git a/tech_report.tex b/tech_report.tex index e1ea5c72..7615be45 100644 --- a/tech_report.tex +++ b/tech_report.tex @@ -31,7 +31,7 @@ Imagine you have two files, $A$ and $B$, and you wish to update $B$ to be the same as $A$. The obvious method is to copy $A$ onto $B$. Now imagine that the two files are on machines connected by a slow -communications link, for example a dial up IP link. If $A$ is large, +communications link, for example a dialup IP link. If $A$ is large, copying $A$ onto $B$ will be slow. To make it faster you could compress $A$ before sending it, but that will usually only gain a factor of 2 to 4. @@ -133,7 +133,7 @@ possible offsets within a file in a ``rolling'' fashion, with very little computation at each point. Despite its simplicity, this checksum was found to be quite adequate as -a first level check for a match of two file blocks. We have found in +a first-level check for a match of two file blocks. We have found in practice that the probability of this checksum matching when the blocks are not equal is quite low. This is important because the much more expensive strong checksum must be calculated for each block where @@ -158,16 +158,16 @@ contains a null value if no element of the list has that hash value. At each offset in the file the 32-bit rolling checksum and its 16-bit hash are calculated. If the hash table entry for that hash value is -not a null value, the second level check is invoked. +not a null value, the second-level check is invoked. -The second level check involves scanning the sorted checksum list +The second-level check involves scanning the sorted checksum list starting with the entry pointed to by the hash table entry, looking for an entry whose 32-bit rolling checksum matches the current value. The scan terminates when it reaches an entry whose 16-bit hash -differs. If this search finds a match, the third level check is +differs. If this search finds a match, the third-level check is invoked. -The third level check involves calculating the strong checksum for the +The third-level check involves calculating the strong checksum for the current offset in the file and comparing it with the strong checksum value in the current list entry. If the two strong checksums match, we assume that we have found a block of $A$ which matches a block of @@ -246,14 +246,14 @@ The columns in the table are as follows: \begin{description} \item [block size] The size in bytes of the checksummed blocks. \item [matches] The number of times a block of $B$ was found in $A$. -\item [tag hits] The number of times the 16 bit hash of the rolling +\item [tag hits] The number of times the 16-bit hash of the rolling checksum matched a hash of one of the checksums from $B$. -\item [false alarms] The number of times the 32 bit rolling checksum +\item [false alarms] The number of times the 32-bit rolling checksum matched but the strong checksum didn't. \item [data] The amount of file data transferred verbatim, in bytes. -\item [written] The total number of bytes written by $\alpha$ +\item [written] The total number of bytes written by $\alpha$, including protocol overheads. This is almost all file data. -\item [read] The total number of bytes read by $\alpha$ including +\item [read] The total number of bytes read by $\alpha$, including protocol overheads. This is almost all checksum information. \end{description} @@ -269,7 +269,7 @@ case. Each pair of checksums consumes 20 bytes: 4 bytes for the rolling checksum plus 16 bytes for the 128-bit MD4 checksum. The number of false alarms was less than $1/1000$ of the number of -true matches, indicating that the 32 bit rolling checksum is quite +true matches, indicating that the 32-bit rolling checksum is quite good at screening out false matches. The number of tag hits indicates that the second level of the -- 2.34.1