Tribblix: manual page: rdist.1

RDIST(1) User Commands RDIST(1)

NAME

rdist - remote file distribution program

SYNOPSIS

rdist [-b] [-D] [-h] [-i] [-n] [-q] [-R] [-a] [-K] [-x]
[-PN | -PO] [-k realm] [-v] [-w] [-y]
[-d macro = value] [-f distfile] [-m host]...

rdist [-b] [-D] [-h] [-i] [-n] [-q] [-R] [-a] [-K] [-x]
[-PN | -PO] [-k realm] [-v] [-w] [-y] -c pathname...
[login @] hostname [: destpath]

DESCRIPTION

The rdist utility maintains copies of files on multiple hosts. It
preserves the owner, group, mode, and modification time of the master
copies, and can update programs that are executing. (rdist does not
propagate ownership or mode changes when the file contents have not
changed.) Normally, a copy on a remote host is updated if its size or
modification time differs from the original on the local host. With
the -y option (younger mode), only the modification times are
checked, not the size. See OPTIONS below.

There are two forms of the rdist command. In the first form shown in
the SYNOPSIS section above, rdist reads the indicated distfile for
instructions on updating files and/or directories. If distfile is
`-', the standard input is used. If no -f option is present, rdist
first looks in its working directory for distfile, and then for
Distfile, for instructions.

The second form shown in SYNOPSIS uses the -c option and specifies
paths as command line options.

The user can opt for a secure session of rdist which uses Kerberos V5
for authentication. Encryption of the data being transferred is also
possible. The rdist session can be kerberized using any of the
following Kerberos specific options : -a, -PN or -PO, -x, and -k
realm. Some of these options (-a, -x, -PN or -PO, and -f or -F) can
also be specified in the [appdefaults] section of krb5.conf(5). The
usage of these options and the expected behavior is discussed in the
OPTIONS section below. If Kerberos authentication is used,
authorization to the account is controlled by rules in
krb5_auth_rules(7). If this authorization fails, fallback to normal
rdist using rhosts occurs only if the -PO option is used explicitly
on the command line or is specified in krb5.conf(5). Also notice that
the -PN or -PO, -x, and -k realm options are just supersets of the -a
option. In order to use the non-secure version of rdist across
machines, each host machine must have a /etc/host.equiv file, or the
user must have an entry in the .rhosts file in the home directory.
See hosts.equiv(5) for more information.

OPTIONS

The following options are supported:

-a

This option explicitly enables Kerberos authentication and trusts
the .k5login file for access-control. If the authorization check
by in.rshd(8) on the server-side succeeds and if the .k5login
file permits access, the user is allowed to carry out the rdist
transfer.

-b

Binary comparison. Performs a binary comparison and updates files
if they differ, rather than merely comparing dates and sizes.

-c pathname ...[login@]hostname[:destpath]

Copies each pathname to the named host; if destpath is specified,
it does not update any pathname on the named host. (Relative
filenames are taken as relative to your home directory.) If the
`login@' prefix is given, the update is performed with the user
ID of login. If the `:destpath' is given, the remote file is
installed as that pathname.

-d macro=value

Defines macro to have value. This option is used to define or
override macro definitions in the distfile. value can be the
empty string, one name, or a list of names surrounded by
parentheses and separated by white space.

-D

Enables debugging.

-f distfile

Uses the description file distfile. A `-' as the distfile
argument denotes the standard input.

-h

Follows symbolic links. Copies the file that the link points to
rather than the link itself.

-i

Ignores unresolved links. rdist normally tries to maintain the
link structure of files being transferred and warn the user if
all the links cannot be found.

-k realm

Causes rdist to obtain tickets for the remote host in realm
instead of the remote host's realm as determined by krb5.conf(5).

-K

This option explicitly disables Kerberos authentication. It can
be used to override the autologin variable in krb5.conf(5).

-m host

Limits which machines are to be updated. Multiple -m arguments
can be given to limit updates to a subset of the hosts listed in
the distfile.

-n

Prints the commands without executing them. This option is useful
for debugging a distfile.

-PO
-PN

Explicitly requests new (-PN) or old (-PO) version of the
Kerberos "rcmd" protocol. The new protocol avoids many security
problems prevalent in the old one and is regarded much more
secure, but is not interoperable with older (MIT/SEAM) servers.
The new protocol is used by default, unless explicitly specified
using these options or through krb5.conf(5). If Kerberos
authorization fails when using the old "rcmd" protocol, there is
fallback to regular, non-kerberized rdist. This is not the case
when the new, more secure "rcmd" protocol is used.

-q

Quiet mode. Does not display the files being updated on the
standard output.

-R

Removes extraneous files. If a directory is being updated,
removes files on the remote host that do not correspond to those
in the master (local) directory. This is useful for maintaining
truly identical copies of directories.

-v

Verifies that the files are up to date on all the hosts. Any
files that are out of date are displayed, but no files are
updated, nor is any mail sent.

-w

Whole mode. The whole file name is appended to the destination
directory name. Normally, only the last component of a name is
used when renaming files. This preserves the directory structure
of the files being copied, instead of flattening the directory
structure. For instance, renaming a list of files such as
dir1/dir2 to dir3 would create files dir3/dir1 and dir3/dir2
instead of dir3 and dir3. When the -w option is used with a
filename that begins with ~, everything except the home directory
is appended to the destination name.

-x

Causes the information transferred between hosts to be encrypted.
Notice that the command is sent unencrypted to the remote system.
All subsequent transfers are encrypted.

-y

Younger mode. Does not update remote copies that are younger than
the master copy, but issues a warning message instead. Only
modification times are checked. No comparison of size is made.

USAGE

White Space Characters

NEWLINE, TAB, and SPACE characters are all treated as white space; a
mapping continues across input lines until the start of the next
mapping: either a single filename followed by a `->' or the opening
parenthesis of a filename list.

Comments

Comments begin with # and end with a NEWLINE.

Distfiles

The distfile contains a sequence of entries that specify the files to
be copied, the destination files to be copied, the destination hosts,
and what operations to perform to do the updating. Each entry has one
of the following formats:

variable_name '=' name_list
[ label: ] source_list '->' destination_list command_list
[ label: ] source_list '::' time_stamp_file command_list

The first format is used for defining variables. The second format is
used for distributing files to other hosts. The third format is used
for making lists of files that have been changed since some given
date. The source list specifies a list of files and/or directories on
the local host that are to be used as the master copy for
distribution. The destination list is the list of hosts to which
these files are to be copied. Each file in the source list is added
to a list of changes if the file is out of date on the host that is
being updated (second format) or if the file is newer than the time
stamp file (third format). Labels are optional. They are used to
identify a command for partial updates. The colon (:) is used after
an optional label, while the double colon (::) is used for making
lists of files that have been changed since a certain date (specified
by the date/time of the time_stamp file). Typically, only notify is
used with the '::' format of the command line.

Macros

rdist has a limited macro facility. Macros are only expanded in
filename or hostname lists, and in the argument lists of certain
primitives. Macros cannot be used to stand for primitives or their
options, or the `->' or `::' symbols.

A macro definition is a line of the form:

macro = value

A macro reference is a string of the form:

${macro}

although (as with make(1S)) the braces can be omitted if the macro
name consists of just one character.

Kerberos Access-Control file
For the kerberized rdist session, each user might have a private
authorization list in a file .k5login in their home directory. Each
line in this file should contain a Kerberos principal name of the
form principal/instance@realm. If there is a ~/.k5login file, then
access is granted to the account if and only if the originating user
is authenticated to one of the principals named in the ~/.k5login
file. Otherwise, the originating user is granted access to the
account if and only if the authenticated principal name of the user
can be mapped to the local account name using the authenticated-
principal-name -> local-user-name mapping rules. The .k5login file
(for access control) comes into play only when Kerberos
authentication is being done.

Metacharacters

The shell meta-characters: [, ], {, }, * and ? are recognized and
expanded (on the local host only) just as they are with csh(1).
Metacharacters can be escaped by prepending a backslash.

The ~ character is also expanded in the same way as with csh;
however, it is expanded separately on the local and destination
hosts.

Filenames

File names that do not begin with `/' or `~' are taken to be relative
to user's home directory on each destination host; they are not
relative to the current working directory. Multiple file names must
be enclosed within parentheses.

Primitives

The following primitives can be used to specify actions rdist is to
take when updating remote copies of each file.

install [-b] [-h] [-i] [-R] [-v] [-w] [-y] [newname]

Copy out of date files and directories (recursively). If no
newname operand is given, the name of the local file is given to
the remote host's copy. If absent from the remote host, parent
directories in a filename's path are created. To help prevent
disasters, a non-empty directory on a target host is not replaced
with a regular file or a symbolic link by rdist. However, when
using the -R option, a non-empty directory is removed if the
corresponding filename is completely absent on the master host.

The options for install have the same semantics as their command
line counterparts, but are limited in scope to a particular map.
The login name used on the destination host is the same as on the
local host unless the destination name is of the format
login@host. In that case, the update is performed under the
username login.

notify address...

Send mail to the indicated email address of the form:

user@host

that lists the files updated and any errors that might have
occurred. If an address does not contain a `@host' suffix, rdist
uses the name of the destination host to complete the address.

except filename ...

Omit from updates the files named as arguments.

except_pat pattern ...

Omit from updates the filenames that match each regular-
expression pattern (see ed(1) for more information on regular
expressions). Note that `\' and `$' characters must be escaped
in the distfile. Shell variables can also be used within a
pattern, however shell filename expansion is not supported.

special [filename] ... "command-line"

Specify a Bourne shell, sh(1) command line to execute on the
remote host after each named file is updated. If no filename
argument is present, the command-line is performed for every
updated file, with the shell variable FILE set to the file's name
on the local host. The quotation marks allow command-line to span
input lines in the distfile; multiple shell commands must be
separated by semicolons (;).

The default working directory for the shell executing each
command-line is the user's home directory on the remote host.

IPv6
The rdist command is IPv6-enabled. See ip6(4P). IPv6 is not currently
supported with Kerberos V5 authentication.

EXAMPLES

Example 1: A Sample distfile

The following sample distfile instructs rdist to maintain identical
copies of a shared library, a shared-library initialized data file,
several include files, and a directory, on hosts named hermes and
magus. On magus, commands are executed as super-user. rdist notifies
merlin@druid whenever it discovers that a local file has changed
relative to a timestamp file. (Parentheses are used when the source
or destination list contains zero or more names separated by white-
space.)

HOSTS = ( hermes root@magus )

FILES = ( /usr/local/lib/libcant.so.1.1
/usrlocal/lib/libcant.sa.1.1 /usr/local/include/{*.h}
/usr/local/bin )

(${FILES}) -> (${HOSTS})
install -R ;
${FILES} :: /usr/local/lib/timestamp
notify merlin@druid ;

FILES

~/.rhosts
User's trusted hosts and users

/etc/host.equiv
System trusted hosts and users

/tmp/rdist*
Temporary file for update lists

$HOME/.k5login
File containing Kerberos principals that are
allowed access

/etc/krb5/krb5.conf
Kerberos configuration file

DIAGNOSTICS

A complaint about mismatch of rdist version numbers might really stem
from some problem with starting your shell, for example, you are in
too many groups.

WARNINGS

The super-user does not have its accustomed access privileges on NFS
mounted file systems. Using rdist to copy to such a file system might
fail, or the copies might be owned by user "nobody".

BUGS

Source files must reside or be mounted on the local host.

There is no easy way to have a special command executed only once
after all files in a directory have been updated.

Variable expansion only works for name lists; there should be a
general macro facility.

rdist aborts on files that have a negative modification time (before
Jan 1, 1970).

There should be a "force" option to allow replacement of non-empty
directories by regular files or symlinks. A means of updating file
modes and owners of otherwise identical files is also needed.

September 12, 2020 RDIST(1)