1YPSERV(8) YPSERV(8)
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6 ypxfr - transfer NIS database from remote server to local host
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9 /usr/lib64/yp/ypxfr [ -f ] [ -c ] [ -d target domain ]
10 [ -h source host ] [ -s source domain ]
11 [ -C taskid program-number ipaddr port ]
12 [ -p yp_path ] mapname ...
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16 ypxfr copies an NIS database from one NIS server to the local host by
17 using the NIS service. ypxfr is generally invoked by ypinit or by
18 ypserv, when ypserv receives a map transfer request from yppush. It
19 creates a temporary map in the directory /var/yp/domain (this direc‐
20 tory must already exist; domain is the default domainname for the
21 local host), fills it by getting the map's entries and fetches the map
22 parameters (master and order number). If the transfer was successful,
23 the old version of the map will be deleted and the temporary copy will
24 be moved into its place. Then, ypxfr will attempt to send a "clear
25 current map" request to the local ypserv.
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27 If run interactively, ypxfr writes its output to stderr. However, if
28 it is invoked without a controlling terminal, it will log the output to
29 syslog.
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31 ypxfr is used primarily in environments where several NIS servers are
32 in use. For all maps, you have a NIS master server, which maintains a
33 canonical copy of the NIS map, and all the other servers, the NIS
34 slaves, copy the new version of the map from the master whenever a
35 update was made. Normally, you have one NIS master for all maps.
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37 In order to maintain consistency across all NIS servers, ypxfr can be
38 run periodically in a cron job. Maps which change infrequently need
39 only be updated once a day (preferably late at night when system usage
40 is lowest), where those with frequent changes (such as passwd.byname
41 and passwd.byuid ) should be updated perhaps once every hour. Examples
42 are in /usr/lib64/yp: ypxfr_1perday, ypxfr_2perday, and ypxfr_1perhour.
43 They can serve as reasonable first cuts.
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45 Normally all updates should be propagated by yppush when /var/yp/Make‐
46 file is run on the NIS master server, however it is a good practice on
47 large networks where possible outages could cause NIS slaves to fall
48 out of sync with the master.
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53 The following options are supported:
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55 -f Force a map transfer. Normally, ypxfr will not transfer a map if
56 it determines that the NIS master's copy is not newer than the
57 existing copy already on the local host. This flag forces a
58 transfer regardless of which server's version is more recent.
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60 -c Do not send a "clear current map" request to the ypserv process
61 running on the local host. This flag is normally used when
62 invoking ypxfr by ypinit or if ypserv is not running locally
63 at the time you are running ypxfr. Otherwise, ypxfr will com‐
64 plain that it cannot talk to the local ypserv, and the transfer
65 will fail.
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67 -d domain
68 Specify a domain other than the default NIS domain.
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70 -h source host
71 Get the map from host, regardless of what the map says the mas‐
72 ter is. If host is not specified, ypxfr asks the NIS service
73 for the name of the master, and tries to get the map from there.
74 This option is used to insure that ypxfr only copies maps from
75 the NIS master server.
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77 -s source domain
78 Specify a source domain from which to transfer a map that should
79 be the same across domains.
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81 -C taskid progam-number ipaddr port
82 This option is only for use by ypserv . When ypserv invokes
83 ypxfr, it specifies that ypxfr should call back a yppush process
84 at the host with IP address ipaddr, registered as program number
85 progam-number, listening on port port, and waiting for a
86 response to transaction taskid.
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88 -p yp_path
89 Change the directory for the maps to yp_path/[domainname]/, the
90 default is /var/yp/[domainname].
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92 mapname
93 One or more names of the map to transfer.
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96 /var/yp/[domainname]/[maps]
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99 ypserv(8), yppush(8), ypinit(8), cron(8), crontab(5)
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102 Thorsten Kukuk <kukuk@suse.de>
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106YP Server August 2001 YPSERV(8)