NAME
ypxfr, ypxfr_1perday, ypxfr_1perhour, ypxfr_2perday — transfer NIS database from server to local node
SYNOPSIS
/usr/sbin/ypxfr
[b]
[-c]
[-d
domain]
[-f]
[-h
host]
[-s
domain]
[-C
tid
prog
ipaddr
port]
mapname
Remarks
The Network Information Service (NIS) was formerly known as Yellow Pages (yp).
Although the name has changed, the functionality of the
service remains the same.
DESCRIPTION
ypxfr
copies a Network Information Service (NIS)
map (database) to the local host from a NIS
server by using the NIS services.
A map can be copied regardless of its age,
or it can be copied depending on whether its modification time
(order number) is more recent than that of the local map.
The
ypxfr
command creates a temporary map in directory
/var/yp/domain
where
domain
is the NIS
domain.
The
ypxfr
command fills the map with
mapname
entries, obtains the map parameters (master and order number),
and loads them.
It then clears the old version of
mapname
and moves the temporary map to the existing
mapname.
If
ypxfr
is run interactively, it writes messages to standard output.
If
ypxfr
is invoked without a controlling terminal and if the log file
/var/yp/ypxfr.log
exists,
ypxfr
appends all its messages to that file.
Since
ypxfr
is usually run from root's
crontab
file (see
crontab(1))
or by
yppush
(see
yppush(1M)),
the log file can retain a record of what
ypxfr
attempted and what the results were.
To maintain consistency between NIS servers,
ypxfr
should be executed periodically for every map in the NIS.
Different maps change at different rates.
For example, the
services.byname
map may not change for months at a time,
and might therefore be checked for changes only once a day,
such as in the early morning hours.
However,
passwd.byname
may change several times per day,
so hourly checks for updates might be more appropriate.
A
crontab
file can perform these periodic checks and transfers automatically.
Rather than having a separate
crontab
file for each map,
ypxfr
requests can be grouped in a shell script
to update several maps at once.
Example scripts (mnemonically named) are in
/var/yp:
ypxfr_1perday,
ypxfr_2perday,
and
ypxfr_1perhour.
They serve as reasonable rough drafts that can be changed as appropriate.
Refer to
ypfiles(4)
and
ypserv(1M)
for an overview of the Network Information Service.
Options
ypxfr
recognizes the following options:
- -b
Preserve the resolver flag in the map during transfer.
- -c
Do not send a "clear current map" request to the local
ypserv
process.
Use this flag if
ypserv
is not running locally when you are running
ypxfr.
Otherwise,
ypxfr
complains that it cannot talk to the local
ypserv,
and the transfer fails.
If
ypserv
is running locally, do not use this flag.
- -d domain
Copy the map from a NIS server in
domain
rather than the
domain
returned by
domainname
(see
domainname(1)).
- -f
Force the map to be copied, even if its order number at the remote NIS
server is not more recent than the order number of the local map.
- -h host
Obtain the map from
host,
regardless of its master server.
If this option is not used,
ypxfr
asks the NIS
service for the master's host name and tries to obtain its map.
The
host
can be a name or an IP address of the form
a.b.c.
d.
- -s domain
Specify a source domain from which to transfer a map that should be
the same across domains (such as the
services.byname
map.
- -C tid prog ipaddr port
This option is used only by
ypserv.
When
ypserv
invokes
ypxfr,
it specifies that
ypxfr
should call back a
yppush
process (that initiated the transfer) at the host with IP address
ipaddr,
registered as program number
prog,
listening on port
port,
and waiting for a response to transaction
tid.
AUTHOR
ypxfr
was developed by Sun Microsystems, Inc.
FILES
- /usr/sbin/ypxfr.log
Log file
The following scripts are suggested for use with
cron.
- /usr/sbin/ypxfr_1perday
Run one transfer per day
- /usr/sbin/ypxfr_2perday
Run two transfers per day
- /usr/sbin/ypxfr_1perhour
Hourly transfers of "volatile" maps
Printable version
