jdbdump(8)jdbdump(8)NAMEjdbdump - Dumps fields from the DHCP dynamic databases.
/usr/sbin/jdbdump [-a] [-c] [-e] [-f character] [-k key] [-s date]
Dumps dates in a readable form. The default is to dump all date-time
fields as UCT (seconds since GMT 1/1/70 00:00). Display currently
active leases only. Display expired leases only. Uses character as
the field separator. The default is the pipe (|) character. Requests
that a specific record with the given key be dumped. The key has three
fields: the client's hardware type, hardware address, and IP address of
its subnet. These three components should be separated by whitespace
and enclosed within quotes (otherwise the shell will create multiple
words). Dumps records timestamped since date. The default is to dump
all the records regardless of the date of last modification.
The jdbdump command reads the databases used by the joind daemon to
store information on client IP address leases and dynamic names and
prints selected fields. Each record is terminated by a newline, and
the fields within each record delimited by default with the pipe (|)
character, although this may be changed with the -f command line
option. Date fields are displayed in Universal Coordinated Time (UCT),
seconds since 00:00 01/01/1970 GMT, unless the -a option is given,
which alters the format to a more readable form.
The following fields are always dumped: This is the identifier which
uniquely identifies the client. It may be the client's MAC address or
an opaque object, uninterpreted by the JOIN software. If nonzero, then
the client id is the MAC address of the client corresponding to this
type. If zero, then the client id may be any byte array which serves
to uniquely identify the client. The length of the identifier in 8-bit
bytes. Note that if the client id corresponds to a MAC address then
this field is redundant. But in the more general case, it may be needed
in order to determine whether the client id is to be interpreted as a
literal or as a decimal or hexadecimal encoding of a byte string.
Resolving this ambiguity becomes important when a file produced by jdb‐
dump has to be reloaded into the database by jdbmod. The IP address
assigned to the client. If this value is null or 0.0.0.0 it means
“none”. The presence of this value does not necessarily mean that the
client is actually at this address. Even when the lease is unexpired,
clients may hold valid leases on addresses for more than one network.
If the client has assignments on n different networks, then jdbdump
will generally dump n different records for that one client. The time
at which this lease began. The time at which this lease will expire.
The time at which this lease may be renewed. Requests to renew the
lease prior to this will be answered by a reply determined by the
residual time remaining on the lease until expiration. After this time
has passed, the client will receive an entirely new lease whose dura‐
tion is determined by the bootptab database. Time when client last
acquired or renewed this lease. IP address of server “owning” the
lease. The client's name (without the domain name). The client's
domain (without the leaf name). If a client's fully qualified domain
name were a.b.c.d, the hostname field would contain a and the domain
field would contain b.c.d. These fields are any fields given by the
command line tag arguments. These tags identify DHCP configuration
parameters. They may be numeric, a two character symbol, or the param‐
eter's long name. See RFC2132 for the numerical values or see
bootptab(4) for the symbolic or long names. Note that the values
dumped are those that the client would have were it to occupy this IP
address. It does not necessarily mean that the client is presently
operating with those values.
Following these fields are any fields given by the command line “tag”
arguments. These tags identify DHCP configuration parameters. They may
be numeric, a two character symbol, or the parameter's long name. Con‐
sult RFC1533 for the numerical values or see bootptab(4) for the sym‐
bolic or long names.
Commands: jdbmod(8), joind(8)