NDB(6) NDB(6)
NAME
ndb - Network database
DESCRIPTION
The network database consists of files describing machines
known to the local installation and machines known publicly.
The files comprise multi-line tuples made up of
attribute/value pairs of the form attr=value or sometimes
just attr. Each line starting without white space starts a
new tuple. Lines starting with # are comments.
The file /lib/ndb/local is the root of the database. Other
files are included in the database if a tuple with an
attribute-value pair of attribute database and no value
exists in /lib/ndb/local. Within the database tuple, each
tuple with attribute file identifies a file to be included
in the database. The files are searched in the order they
appear. For example:
database=
file=/lib/ndb/common
file=/lib/ndb/local
file=/lib/ndb/global
declares the database to be composed of the three files
/lib/ndb/common, /lib/ndb/local, and /lib/ndb/global. By
default, /lib/ndb/local is searched before the others. How-
ever, /lib/ndb/local may be included in the database to
redefine its ordering.
Within tuples, pairs on the same line bind tighter than
pairs on different lines.
The program ndb/cs (see ndb(8)) and the library routine
ipinfo (see ndb(2)) perform searches for information rela-
tive to a particular host. Ndb/cs resolves meta-addresses
of the form $attribute by returning the value from the
attribute=value most closely related to the resolving host.
The attribute-value pair comes from the tuple for the sys-
tem, its subnet, or its network with the system tuple having
precedence, subnet next, and network last.
A number of attributes are meaningful to programs and thus
reserved. They are:
sys system name
dom Internet domain name
ip Internet address
ether Ethernet address
dk Datakit address
Page 1 Plan 9 (printed 12/21/24)
NDB(6) NDB(6)
bootf file to download for initial bootstrap
ipnet Internet network name
ipmask Internet network mask
ipgw Internet gateway
auth authentication server to be used
fs file server to be used
tcp a TCP service name
udp a UDP service name
il an IL service name
port a TCP, UDP, or IL port number
restricted a TCP service that can be called only by ports
numbered less that 1024
proto a protocol supported by a host. The pair
proto=il is needed by cs (see ndb(8)) in tuples
for hosts that support the IL protocol.
9P parameters for the 9P file protocol, in particu-
lar whether the server authenticates (9P=auth).
The file /lib/ndb/auth is used during authentication to
decide who has the power to `speak for' other users; see
auth(6).
EXAMPLES
A tuple for the CPU server, spindle.
sys = spindle
dom=spindle.research.att.com
bootf=/mips/9powerboot
ip=135.104.117.32 ether=080069020677
dk=nj/astro/spindle
proto=il
Entries for the network mh-astro-net and its subnets.
ipnet=mh-astro-net ip=135.104.0.0 ipmask=255.255.255.0
fs=bootes.research.att.com
ipgw=r70.research.att.com
auth=p9auth.research.att.com
ipnet=unix-room ip=135.104.117.0
ipgw=135.104.117.1
ipnet=third-floor ip=135.104.51.0
ipgw=135.104.51.1
Mappings between TCP service names and port numbers.
tcp=sysmon port=401
tcp=rexec port=512 restricted
tcp=9fs port=564
FILES
/lib/ndb/local
first database file searched
Page 2 Plan 9 (printed 12/21/24)
NDB(6) NDB(6)
/lib/ndb/global
second database file searched
SEE ALSO
dial(2), ndb(2), ndb(8), bootp(8), ipconfig(8), con(1)
Page 3 Plan 9 (printed 12/21/24)