HP-UX Reference (11i v3 07/02) - 1 User Commands N-Z (vol 2)

n
nsupdate(1) nsupdate(1)
(BIND 9.3)
NAME
nsupdate - Dynamic DNS update utility
SYNOPSIS
nsupdate [-dv][-k
keyfile | -y keyname:secret][-r udpretries][-t
timeout]
[
-u udptimeout][filename]
DESCRIPTION
nsupdate submits Dynamic DNS update requests to a name server, as defined in RFC 2136. This allows
resource records to be added to or removed from a zone without manually editing the zone file. A single
update request can contain requests to add or remove more than one resource record.
Zones that are under dynamic control via nsupdate
or a DHCP server should not be edited by hand.
Manual edits could conflict with dynamic updates and cause data to be lost.
The resource records that are dynamically added or removed with
nsupdate have to be in the same zone.
Requests are sent to the zone’s master server. This is identified by the
MNAME field of the zone’s
SOA
record.
Transaction signatures can be used to authenticate the Dynamic DNS updates. These use the
TSIG
resource record type described in RFC 2845 or the SIG(0) record described in RFC 2535 and RFC 2931.
TSIG relies on a shared secret that should only be known to nsupdate and the name server. Currently,
the only supported encryption algorithm for TSIG is HMAC-MD5, which is defined in RFC 2104.
Once other algorithms are defined for TSIG, applications will need to ensure they select the appropriate
algorithm as well as the key when authenticating each other. For instance, suitable
key{} and
server{} statements would be added to /etc/named.conf
so that the name server can associate the
appropriate secret key and algorithm with the IP address of the client application that will be using
TSIG
authentication. SIG(0) uses public key cryptography. To use a SIG(0) key, the public key must be stored in
a
KEY record in a zone served by the name server. nsupdate does not read /etc/named.conf
.
Options
-d Operate in debug mode. This provides tracing information about the update requests that are
made and the replies received from the name server.
-k keyfile
Provide the shared secret needed to generate a TSIG record for authenticating Dynamic DNS
update requests. With this option,
nsupdate reads the shared secret from the file keyfile,
whose name is of the form
Kname.+157.+random.private
For historical reasons, the file Kname.+157.+random.key must also be present. This option
is mutually exclusive with the -y option. -k may also be used to specify a SIG(0) key used to
authenticate Dynamic DNS update requests. In this case, the key specified is not an
HMAC-MD5
key.
-r udpretries
Set the number of UDP retries. The default is 3. If set to zero only one update request will be
made.
-t timeout
Set the maximum time in seconds a update request can take before it is aborted. The default is
300 seconds. Zero can be used to disable the timeout.
-u udptimeout
Set the UDP retry interval in seconds. The default is 3 seconds. If set to zero the interval will
be computed from the timeout interval and number of UDP retries.
-v Use a TCP connection to send update requests to the name server. By default, nsupdate uses
UDP to send update requests. This may be preferable when a batch of update requests is made.
-y keyname:secret
Generate a signature from keyname and secret. keyname is the name of the key, and secret is
the base-64-encoded shared secret. The use of the -y option is discouraged because the shared
secret is supplied as a command line argument in clear text. This may be visible in the output
from ps(1) or in a history file maintained by the user’s shell.
68 Hewlett-Packard Company − 1 − HP-UX 11i Version 3: February 2007