System Administration Commands ypserv(1M)
NAME
ypserv, ypxfrd - NIS server and binder processes
SYNOPSIS
/usr/lib/netsvc/yp/ypserv [-dv] [-i | -I] [-r | -R]
/usr/lib/netsvc/yp/ypxfrd
DESCRIPTION
The Network Information Service (NIS) provides a simple net-
work lookup service consisting of databases and processes. The databases are ndbm files in a directory tree rooted at /var/yp. See ndbm(3C). These files are described in ypfiles(4). The processes are /usr/lib/netsvc/yp/ypserv, the NIS database lookup server, and /usr/lib/netsvc/yp/ypbind,the NIS binder. The programmatic interface to the NIS ser-
vice is described in ypclnt(3NSL). Administrative tools are described in yppoll(1M), yppush(1M), ypset(1M), ypxfr(1M), and ypwhich(1). Tools to see the contents of NIS maps are described in ypcat(1), and ypmatch(1). Database generation and maintenance tools are described in ypinit(1M), ypmake(1M), and makedbm(1M). The ypserv utility is a daemon process typically activated at system startup from svc:/network/nis/server:default. Alternatively, you can, as the root user, start NIS servicesusing ypstart(1M) from the command-line. ypserv runs only on
NIS server machines with a complete NIS database. You can halt all NIS services using the ypstop(1M) command.The ypxfrd utility transfers entire NIS maps in an efficient
manner. For systems that use this daemon, map transfers are 10 to 100 times faster, depending on the map. To use thisdaemon, be sure ypxfrd is running on the master server. See
/usr/lib/netsvc/yp/ypstart. ypxfr attempts to use ypxfrd
first. If that fails, it prints a warning, then uses the older transfer method.The ypserv daemon's primary function is to look up informa-
tion in its local database of NIS maps. The operations performed by ypserv are defined for the implementor by the YP Protocol Specification, and for theprogrammer by the header file
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System Administration Commands ypserv(1M) Communication to and from ypserv is by means of RPC calls.Lookup functions are described in ypclnt(3NSL), and are sup-
plied as C-callable functions in the libnsl(3LIB) library.
There are four lookup functions, all of which are performedon a specified map within some NIS domain: yp_match(3NSL),
yp_first(3NSL), yp_next(3NSL), and yp_all(3NSL). The
yp_match operation takes a key, and returns the associated
value. The yp_first operation returns the first key-value
pair from the map, and yp_next can be used to enumerate the
remainder. yp_all ships the entire map to the requester as
the response to a single RPC request. A number of special keys in the DBM files can alter the way in which ypserv operates. The keys of interest are:YP_INTERDOMAIN The presence of this key causes ypserv
to forward to a DNS server host lookups that cannot be satisfied by the DBM files.YP_SECURE This key causes ypserv to answer only
questions coming from clients on reserved ports.YP_MULTI_hostname This is a special key in the form,
YP_MULTI_hostname addr1,...,addrN. A
client looking for hostname receives the closest address. Two other functions supply information about the map, ratherthan map entries: yp_order(3NSL), and yp_master(3NSL). In
fact, both order number and master name exist in the map askey-value pairs, but the server will not return either
through the normal lookup functions. If you examine the map with makedbm(1M), however, they are visible. Other functions are used within the NIS service subsystem itself, and are not of general interest to NIS clients. These functionsinclude do_you_serve_this_domain?, transfer_map, and
reinitialize_internal_state.
On start up, ypserv checks for the existence of the NIS toLDAP (N2L) configuration file /var/yp/NISLDAPmapping. If it is present then a master server starts in N2L mode. If the file is not present it starts in "traditional" (non N2L) mode. Slave servers always start in traditional mode.
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System Administration Commands ypserv(1M)In N2L mode, a new set of map files, with an LDAP_ prefix,
are generated, based on the contents of the LDAP DIT. The old map files, NIS source files and ypmake(1M) are not used. It is possible that ypmake(1M) can be accidentally run in N2L mode. If the occurs, the old style map files are overwritten. That the map files are overwritten is harmless.However, any resulting yppush(1M) operation will push infor-
mation based on the DIT rather than the source files. The user may not expect information based on the DIT. ypserv keeps track of the last modification date of the old style map files. If the map files have been updated, a warning is logged that suggests that the user call yppush directly instead of ypmake. If a server attempts to run in N2L mode and a LDAP server cannot be contacted, it behaves as follows: 1. When ypserv is started, a warning will be logged. 2. When a NIS read access is made and the TTL entry has expired, a warning is logged.Information that is returned from the cache has not been updated. 3. When a NIS write access is made, a warning is logged. The cache will not be updated, and a NIS failure will be returned.If ypxfrd is running in N2L mode and is asked to transfer a
map, ypxfrd first checks whether the map is out of date. If
the map is out of date, ypxfrd initiates an update from the
DIT. ypxfrd cannot wait for the update to complete. If
ypxfrd waited, the client end ypxfr operation could time
out. To prevent ypxfrd from timing out, the existing map is
transferred from the cache. The most up to date map will betransferred on subsequent ypxfrd operations.
OPTIONS ypserv-d The NIS service should go to the DNS for more host
information. This requires the existence of a correct /etc/resolv.conf file pointing to a DNS server. This option turns on DNS forwarding regardless of whetheror not the YP_INTERDOMAIN flag is set in the hosts
maps. See makedbm(1M). In the absence of an /etc/resolv.conf file, ypserv complains, but ignoresthe -d option.
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System Administration Commands ypserv(1M)-i If in N2L mode, initialize the NIS related parts of
the DIT based on the current, non LDAP_ prefixed, map
files. The LDAP_ prefixed maps are not created or
updated. If you require that LDAP_ prefixed maps be
updated or created, then use the -ir option.
The -i option does not attempt to create any NIS
domain or container objects. If any NIS domain or container objects have not already been created, thenerrors will occur, as entries are written to nonex-
istent containers.-I Identical to -i, except that any missing domain and
container objects are created.-r If in N2L mode, then refresh the LDAP_ prefixed map
files based on the contents of the DIT.-ir If both -i and -r are specified in N2L mode, then the
DIT will first be initialized from the current nonLDAP_ prefixed map files. A new set of LDAP_ prefixed
maps will then be generated from the contents of theDIT. A new set of LDAP_ prefixed maps is required
when moving from traditional NIS to N2L mode NIS.-Ir Identical to -ir, except that any missing domain and
container objects are created.-v Operate in the verbose mode, printing diagnostic mes-
sages to stderr.When run with the -i, -r, -I, -ir or -Ir options, the ypserv
command runs in the foreground and exits once map initiali-
zation has been completed. Once the ypserv command exits, the user knows the maps are ready and can restart ypserv and the other yp daemons by running ypstart(1M). If there is a requirement to initialize the DIT from the NIS source files, which may have been modified since the mapswere last remade, run ypmake before running ypserv -i or
ypserv -ir. ypmake regenerated old style NIS maps. Then
ypserv -ir dumps them into the DIT. When the -ir option is
used, the LDAP_ prefixe maps are also generated or updated.
Since these maps will be more recent than the old styleSunOS 5.11 Last change: 15 Dec 2004 4
System Administration Commands ypserv(1M) maps, ypmake will not be reported as erroneous when it is run. FILES /var/yp/securenets Defines the hosts and networks that are granted access to information in the served domain. It is read atstartup time by both ypserv and ypxfrd.
/var/yp/ypserv.log If the /var/yp/ypserv.log file exists when ypserv startsup, log information is written to it when error condi-
tions arise. /var/yp/binding/domainname/ypservers Lists the NIS server hosts that ypbind can bind to.ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Availability | service/network/nis ||_____________________________|_____________________________|
SEE ALSO
svcs(1), ypcat(1), ypmatch(1), ypwhich(1), domainname(1M), makedbm(1M), svcadm(1M), ypbind(1M), ypinit(1M), ypmake(1M), yppoll(1M), yppush(1M), ypset(1M), ypstart(1M), ypstop(1M),ypxfr(1M), ndbm(3C), ypclnt(3NSL), libnsl(3LIB), NISLDAPmap-
ping(4), securenets(4), ypfiles(4), ypserv(4), attri-
butes(5), smf(5) NOTESypserv supports multiple domains. The ypserv process deter-
mines the domains it serves by looking for directories of the same name in the directory /var/yp. It replies to all broadcasts requesting yp service for that domain.SunOS 5.11 Last change: 15 Dec 2004 5
System Administration Commands ypserv(1M) The Network Information Service (NIS) was formerly known as Sun Yellow Pages (YP). The functionality of the two remains the same; only the name has changed. The name Yellow Pages is a registered trademark in the United Kingdom of BritishTelecommunications PLC, and must not be used without permis-
sion.NIS uses ndbm() files to store maps. Therefore, it is sub-
ject to the 1024 byte limitations described in the USAGE and
NOTES sections of the ndbm(3C) man page. The NIS server service is managed by the service management facility, smf(5), under the service identifier: svc:/network/nis/server:default Administrative actions on this service, such as enabling, disabling, or requesting restart, can be performed using svcadm(1M). The service's status can be queried using the svcs(1) command.SunOS 5.11 Last change: 15 Dec 2004 6