1YPBIND(8) ypbind-mt YPBIND(8)
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6 ypbind - NIS binding process
7
9 ypbind [-broadcast | -ypset | -ypsetme] [-c] [-f configfile] [-no-ping]
10 [-broken-server] [-local-only]
11 [-i | -ping-interval ping-interval]
12 [-r | -rebind-interval rebind-interval] [-d | -debug]
13 [-v | -verbose] [-n | -foreground] [-p port] [-log log-options]
14 [-no-dbus]
15 ypbind --version
17 ypbind --help
19
21 ypbind finds the server for NIS domains and maintains the NIS binding
22 information. The client (normally the NIS routines in the standard C
23 library) could get the information over RPC from ypbind or read the
24 binding files. The binding files resides in the directory
25 /var/yp/binding and are conventionally named [domainname].[version].
26 The supported versions are 1 and 2. There could be several such files
27 since it is possible for an NIS client to be bound to more than one
28 domain.
29 After a binding has been established, ypbind will send YPPROC_DOMAIN
31 requests to the current NIS server at 20 seconds intervals. If it
32 doesn't get an response or the NIS server reports that he doesn't have
33 this domain any longer, ypbind will search for a new NIS server. All 15
34 minutes ypbind will check to see if the current NIS server is the
35 fastest. If it find a server which answers faster, it will switch to
36 this server. You could tell ypbind to use network broadcasts to find a
37 new server, what is insecure, or you could give it a list of known
38 secure servers. In this case ypbind will send a ping to all servers and
39 binds to first one which answers.
40 Unless the option -debug is used, ypbind detaches itself from the
42 controlling terminal and puts itself into background. ypbind uses
43 syslog(3) for logging errors and warnings. At startup or when receiving
44 signal SIGHUP, ypbind parses the file /etc/yp.conf and tries to use the
45 entries for its initial binding.
46 A broadcast entry in the configuration file will overwrite a
48 ypserver/server entry and a ypserver/server entry broadcast. If all
49 given server are down, ypbind will not switch to use broadcast. ypbind
50 will try at first /etc/hosts and then DNS for resolving the hosts names
51 from /etc/yp.conf. If ypbind couldn't reconfigure the search order, it
52 will use only DNS. If DNS isn't available, you could only use
53 IP-addresses in /etc/hosts. ypbind could only reconfigure the search
54 order with glibc 2.x. If the -broadcast option is specified, ypbind
55 will ignore the configuration file. If the file does not exist or if
56 there are no valid entries, ypbind exit.
57 This ypbind version listens for DBUS messages from NetworkManager. If
59 no NetworkManager is running at startup, ypbind will behave as usual
60 and assumes there is a working network connection. If NetworkManager is
61 running on the system, ypbind will only search and provide NIS
62 informations, if NetworkManager tells that a network connection is
63 available. If NetworkManager establishes a connection, ypbind will
64 reread all configuration files, registers at the local portmapper and
65 try to search NIS servers. If NetworkManager drops a connection, ypbind
66 will unregister from portmapper.
67 In Fedora we use systemd for starting services. We need to finish
69 starting process of ypbind service not before service is fully started,
70 which means ypbind daemon is prepared to answer. There is a test script
71 /usr/libexec/ypbind-post-waitbind used in ypbind.service, that waits
72 for ypbind daemon to be fully connected to NIS server and waits by
73 default up to 45s. Sometimes this is not enough, because network set up
74 can take longer than 45s during boot, so starting ypbind.service fails.
75 User can increase the timeout by setting an environment variable
76 NISTIMEOUT in /etc/sysconfig/ypbind. For example NISTIMEOUT=180 means
77 ypbind will wait up to 180 seconds for binding to a NIS server.
78 Another option is to enable NetworkManager-wait-online.service and add
79 an ordering rule into ypbind.service, ideally by creating
80 /etc/systemd/system/ypbind.service with the following content:
81 .include /lib/systemd/system/ypbind.service
83 [Service]
84 After=NetworkManager-wait-online.service
85
87 -broadcast
88 Send a broadcast to request the information needed to bind to a
89 specific NIS server. With this option, /etc/yp.conf will be
90 ignored.
91 -ypset
93 Allow root from any remote machine to change the binding for a
94 domain via the ypset(8) command. By default, no one can change the
95 binding. This option is really insecure. If you change a binding
96 for a domain, all the current known servers for this domain will be
97 forgotten. If the new server goes down, ypbind will use the old
98 searchlist.
99 -ypsetme
101 The same as -ypset, but only root on the local machine is allowed
102 to change the binding. Such requests are only allowed from
103 loopback.
104 -c
106 ypbind only checks if the config file has syntax errors and exits.
107 -d, -debug
109 starts ypbind in debug mode. ypbind will not put itself into
110 background, and error messages and debug output are written to
111 standard error.
112 -n, -foreground
114 ypbind will not put itself into backgroun.
115 -v, -verbose
117 Causes ypbind to syslog(2) any and all changes in the server its
118 bound to.
119 -broken-server
121 Lets ypbind accept answers from servers running on an illegal port
122 number. This should usually be avoided, but is required by some
123 ypserv(8) versions.
124 -no-ping
126 ypbind will not check if the binding is alive. This option is for
127 use with dialup connections to prevent ypbind from keeping the
128 connection unnecessarily open or causing auto-dials.
129 -f configfile
131 ypbind will use configfile and not /etc/yp.conf
132 -local-only
134 ypbind will only bind to the loopback device and is not reachable
135 from a remote network.
136 -p port
138 Lets ypbind listen on a specified port number, rather than asking
139 portmapper to assing a port for it.
140 -i, -ping-interval ping-interval
142 The default value for ypbind to check, if a NIS server is still
143 reachable, is 20 seconds. With this options another frequency in
144 seconds can be specified.
145 -r, -rebind-interval rebind-interval
147 The default value for ypbind to search for the fastest NIS server
148 is 900 seconds (15 minutes). With this options another frequency in
149 seconds can be specified.
150 -log log-options
152 Allows to log special events. log-options is a logical sum of
153 values for particular events - 1 for logging rpc calls, 2 for
154 logging broken server calls, 4 for logging server changes.
155 -no-dbus
157 Disables DBUS support if compiled in.
158 --version
160 Prints the version number
161
163 /etc/yp.conf
164 configuration file.
165 /var/yp/binding/[domainname].[version]
167 binding file containing information about each NIS domain.
168 /var/run/ypbind.pid
170 contains the process id of the currently running ypbind master
171 process.
172
174 syslog(3), domainname(1), yp.conf(5), ypdomainname(8), ypwhich(1),
175 ypserv(8), ypset(8)
176
178 ypbind-mt was written by Thorsten Kukuk <kukuk@thkukuk.de>.
179ypbind-mt 04/09/2013 YPBIND(8)