ZEPHYRD(8) System Manager's Manual ZEPHYRD(8)NAME
zephyrd - Zephyr server daemon
SYNOPSIS
/usr/etc/zephyrd [ -d ]
DESCRIPTION
zephyrd is the central server for the Zephyr Notification System. It maintains a location database of all currently logged-in users, and a
subscription database for each user's Zephyr clients.
zephyrd communicates with daemons running on other Zephyr server hosts, to provide a reliable service.
While running, any unusual conditions are recorded via syslog(3) to facility local6 at various levels. The -d option enables logging of
additional debugging information.
When a zephyrd is executed, it requests a list of server machines from Hesiod and initializes its state from any zephyrds executing on the
other known servers. This initialization is only performed after the zephyrds have authenticated themselves to each other via Kerberos.
The server then enters a dispatch loop, servicing requests from clients and other servers.
SIGNALS
SIGUSR1 enables logging of additional debugging information.
SIGUSR2 disables the logging of additional debugging information.
SIGHUP causes zephyrd to re-read the default subscription file and to re-query Hesiod about valid peers. Any peers which are not respond-
ing and no longer mentioned in Hesiod are flushed; any peers not previously named by Hesiod are added.
SIGINT and SIGTERM cause zephyrd to gracefully shut down.
SIGFPE causes zephyrd to dump the location and subscription databases to /var/tmp/zephyr.db in an ASCII format.
ACCESS CONTROL
Certain notice classes are restricted by the Zephyr server. Each such class has access control lists enumerating who may transmit
(xmt-*.acl) or subscribe to that particular class. Subscriptions may be restricted either absolutely (sub-*.acl files), or by instance
restrictions. iws-*.acl files control subscriptions to wildcarded instances. iui-*.acl files control subscriptions to instances which are
not the Kerberos principal identity of the subscriber. If an access control list of a given type is absent, there is no restriction of
that type on the class, except that any notices of the class must be authenticated. The class registry lists all classes which are
restricted.
FILES
/etc/zephyr/acl/class-registry.acl:
List of classes which are restricted
/etc/zephyr/acl/iws-*.acl:
Access Control Lists for instance-wildcard restrictions
/etc/zephyr/acl/iui-*.acl:
Access Control Lists for instance-identity restrictions
/etc/zephyr/acl/sub-*.acl:
Access Control Lists for subscribing
/etc/zephyr/acl/xmt-*.acl:
Access Control Lists for transmitting
/etc/zephyr/srvtab:
Kerberos 4 Service keys
/etc/zephyr/krb5.keytab:
Kerberos V Service keys
/etc/zephyr/ztkts:
Current Kerberos tickets for exchange with other servers
/var/tmp/zephyr.db:
File containing an ASCII dump of the database.
BUGS
The current implementation of the Zephyr server (zephyrd(8)) makes no distinction between realm-announced, net-visible and net-announced
exposure levels.
SEE ALSO zephyr(1), zhm(8), kerberosintro(1), hesiod(3), access_control_lists(?), syslog(3)
Athena Technical Plan, Sections E.4.1 (Zephyr Notification Service) and E.2.1 (Kerberos Authentication and Authorization System)
AUTHOR
John T. Kohl, MIT Project Athena and Digital Equipment Corporation
RESTRICTIONS
Copyright (c) 1987,1988 by the Massachusetts Institute of Technology. All Rights Reserved.
zephyr(1) specifies the terms and conditions for redistribution.
MIT Project Athena July 1, 1988 ZEPHYRD(8)
Check Out this Related Man Page
ZWRITE(1) General Commands Manual ZWRITE(1)NAME
zwrite - write to another user via Zephyr
SYNOPSIS
zwrite [ -a ] [ -d ] [ -v ] [ -q ] [ -t ] [ -u ] [ -o ] [ -n ] [ -l ] [ -C ] [ -O opcode ] [ -s signature ] [ -c class ] [ -i instance ] [
-r realm ] [ -f arg ] [ user ... ] [ -m message ]
DESCRIPTION
Zwrite sends a message from you to another user through the zephyr(1) notification service. The user must have subscribed to messages of
the appropriate class and instance using the zctl(1) program.
Zwrite understands the following options.
-a Causes zwrite to send the message authenticated, using Kerberos to perform the authentication. This is the default.
-d Causes zwrite to send the message unauthenticated.
-v Causes zwrite to print what type of message it is sending, and whether or not it was successful.
-q Forces zwrite to suppress information about whether or not the message was sent.
-t Prevents zwrite from expanding tabs in the message into appropriate spaces. Normally zwrite will expand any tabs it finds into
the appropriate number of spaces to maintain separation based on 8-character tab stops.
-l Causes zwrite to ignore `.' on a line by itself in the input and only end a typed message when the user types the end-of-file
character (usually control-D). When the input is not a terminal, this is the default action.
-u Sends an urgent message. This changes the zephyr instance of the message to ``URGENT''.
-o Causes zwrite to ignore the Zephyr variables zwrite-class, zwrite-inst, and zwrite-opcode when picking a default class,
instance, and opcode.
-n prevents zwrite from sending a PING message to verify the recipient is subscribing to messages. By default, zwrite will send a
notice to the destination class, instance, and recipient, with opcode ``PING'' before sending the message. If the PING is
sent, and the server response indicates there are no recipients subscribed to your message, zwrite exits without sending a mes-
sage. When the -n option is used, no PING is sent.
-C prepends a "CC:" line to the body of the message indicating the recipients of the message. This is strictly a convenience: the
presence of a "CC:" line at the top of a zephyr body does not necessarily indicate that this option was used, or that the mes-
sage really was sent to the listed users, and its lack doesn't indicate that the message was not sent to multiple users.
-s signature
sets the signature to be included in the message. This overrides both the user's name (as found in the password file) and any
setting of the Zephyr variable zwrite-signature. signature must be a single argument, hence when using a shell it should be
quoted with double quotes. A signature argument of "" leaves the signature in the message empty.
-c class Allows a user to specify a different class for the message. This allows a message to be sent to a large group of people with
some degree of security. See zephyr(1) and zephyrd(8) for a description of how to restrict access to classes. When this
option is specified, the message is sent to recipient "*" unless an additional list of recipients is specified.
This argument may not be used in conjunction with the -f option.
-i instance Allows a user to specify a different instance than the default. When this option is used, the message is sent to recipient "*"
unless an additional list of recipients is specified. This allows a message to be sent to a large group of people (e.g. a
development group) just by having the members subscribe to messages of class "MESSAGE", the specified instance, and recipient
"*".
This argument may not be used in conjunction with the -f option.
-r realm Allows a user to specify a different realm for the message, if the server supports interrealm Zephyr.
-F format Allows a user to specify a different default format for the message.
-O opcode Allows a user to specify a different opcode for the message. Some Zephyr notice display programs may use the opcode to decide
how to display a notice.
-f arg Allows a user to specify an argument to be interpreted as a filesystem specification. The class is set to FILSRV. he instance
is set to arg as modified: If arg contains no colons (`:'), it is assumed to be a host name, and it is converted into an offi-
cial host name via gethostbyname(3). If arg contains a colon, the portion preceding the colon is treated as a host name, and
the colon and any trailing characters are appended to the offical host name returned by gethostbyname. If the name fails to
resolve into an official host name, the instance is set to arg unmodified.
This option may not be used in conjunction with the -c or -i option.
-m Zwrite sends the remaining arguments on the command line as the message.
If the -m option is not specified, the user is prompted for the message to be sent. The message may be terminated by typing ^D or ``.'' on
a line by itself.
The default class for messages is ``MESSAGE'', the default instance is ``PERSONAL'', andthe default opcode is ``'' (an empty string).
These defaults can be overridden by setting the Zephyr variables zwrite-class, zwrite-inst, and zwrite-opcode, respectively. Command-line
options can override the defaults.
If the class is ``MESSAGE'' and the instance is either ``PERSONAL'' or ``URGENT'', a recipient must be specified. These comparisons are
case-sensitive.
Unless the -s option is used, the contents of the Zephyr variable zwrite-signature are used to augment the user's username in the message.
If zwrite-signature is not set and the -s option is not specified, the user's full name (as specified in the password file) is used
instead.
BUGS
Tab expansion should really be done by the receiver of the message.
The -u option is provided for compatibility with old versions of zwrite and is not necessarily useful for sending messages to users who do
not have old subscription files.
SEE ALSO kerberosintro(1), zctl(1), zephyr(1), zwgc(1), zhm(8), zephyrd(8), gethostbyname(3)
Project Athena Technical Plan Section E.4.1, `Zephyr Notification Service'
FILES
/etc/passwd
$ZEPHYR_VARS or $HOME/.zephyr.vars
AUTHOR
Robert S. French (MIT-Project Athena)
RESTRICTIONS
Copyright (c) 1987,1988 by the Massachusetts Institute of Technology. All Rights Reserved.
zephyr(1) specifies the terms and conditions for redistribution.
MIT Project Athena October 26, 1989 ZWRITE(1)