YPXFR

Section: Maintenance Commands (8)
Updated: 19 April 1986
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NAME

ypxfr, ypxfr_1perday, ypxfr_1perhour, ypxfr_2perday - transfer a YP map from some YP server to here

SYNOPSIS

/usr/etc/yp/ypxfr [ -f ] [ -h host ] [ -d domain ] [ -c ] [ -C tid prog ipadd port ] mapname

DESCRIPTION

ypxfr moves a YP map to the local host by making use of normal YP services. It creates a temporary map in the directory /etc/yp/domain (which must already exist), fills it by enumerating the map's entries, fetches the map parameters (master and order number), and loads them. It then deletes any old versions of the map and moves the temporary map to the real mapname.

If ypxfr is run interactively, it writes its output to the terminal. However, if it is invoked without a controlling terminal, and if the log file /etc/yp/ypxfr.log exists, it will append all its output to that file. Since ypxfr is most often run from /usr/lib/crontab, or by ypserv, you can use the log file to retain a record of what was attempted, and what the results were.

For consistency between servers, ypxfr should be run periodically for every map in the YP data base. Different maps change at different rates: the services.byname map may not change for months at a time, for instance, and may therefore be checked only once a day in the wee hours. You may know that mail.aliases or hosts.byname changes several times per day. In such a case, you may want to check hourly for updates. A crontab(5) entry can be used to perform periodic updates automatically. Rather than having a separate crontab entry for each map, you can group commands to update several maps in a shell script. Examples (mnemonically named) are in /etc/yp: ypxfr_1perday.sh, ypxfr_2perday.sh, and ypxfr_1perhour.sh. They can serve as reasonable first cuts.

Refer to ypfiles(5) and ypserv(8) for an overview of the yellow pages.

OPTIONS

-f: Force the transfer to occur even if the version at the master is not more recent than the local version.
-c: Don't send a "Clear current map" request to the local ypserv process. Use this flag if ypserv is not running locally at the time you are running ypxfr. Otherwise, ypxfr will complain that it can't talk to the local ypserv, and the transfer will fail.
-h host: Get the map from host, regardless of what the map says the master is. If host is not specified, ypxfr will ask the YP service for the name of the master, and try to get the map from there. host may be a name or an internet address in the form a.b.c.d.
-d domain: Specify a domain other than the default domain.
-C tid prog ipadd port: This option is only for use by ypserv. When ypserv invokes ypxfr, it specifies that ypxfr should call back a yppush process at the host with IP address ipaddr, registered as program number prog, listening on port port, and waiting for a response to transaction tid.

FILES

/etc/yp/ypxfr.log: log file
/etc/yp/ypxfr_1perday: script to run one transfer per day, for use with cron(8)
/etc/yp/ypxfr_2perday: script to run two transfers per day
/etc/yp/ypxfr_1perhour: script for hourly transfers of volatile maps

This document was created by man2html, using the manual pages.
Time: 00:58:14 GMT, September 26, 2024