dblist(DCC) LOCAL dblist(DCC)
dblist -- Database List Distributed Checksum Clearinghouse
dblist [-vVHD] [-G on | off] [-h homedir] [-C 'type h1 h2 h3 h4']
[-I server-ID] [-A dbaddr] [-L pathlen] [-P pages] [-T timestamp]
[file1 file2 ...]
Dblist lists the contents of a DCC database as it does some consistency
-v lists more of the database. Additional information is produced with
additional -v arguments.
-V displays the version of the DCC database lister.
-H turns off the listing of the hash table as well as the analysis of
the hash table. Determining the worst case and average lengths of
chains in the hash table can take a long time for a large database
on a small computer.
-D turns off the listing of the data or checksum records.
lists a greylist database.
overrides the default DCC home directory, which is often /var/dcc.
-C 'type h1 h2 h3 h4'
limits the listing to records containing that checksum or one of the
other checksums specified with -C or server-IDs specified with -I.
As many as 16 checksums can be specified.
limits the listing to records with that server-ID or one of the
other server-IDs specified with -I or checksums specified with -C.
As many as 16 server-IDs can be specified.
excludes database records before dbaddr.
excludes records with path lengths shorter than pathlen.
ignores all but the last pages of the database.
excludes records with other timestamps. As many as 16 timestamps
can be specified.
file1 file2 ...
are names of databases to be listed. The default is dcc_db and its
companion, dcc_db.hash in the DCC home directory.
By default, the sizes of the main file and the hash table as well as how
much they contain and values related to the performance of the hash are
With a single -v, most of the mail database file and the contents of mem-
ory mapped server flooding positions in the flod.map file are listed.
The listing starts with the serial number of the database file which is
when old entries were last removed from it by dbclean(8) That is followed
by similar lines showing the oldest timestamp of checksums not expired by
dbclean and of mail that is not "spam."
The flooding positions from the flod.map file are record offsets or
addresses in the main database file.
A typical record in the main database file looks like:
02/07/02 20:25:12.497032 5 auth 1601 2fe5b94
Body 6 e2d3f96a c65aea01 3fece361 edff9ecf 2f21364 772d2
Fuz1 many 6ff56fe8 ffc312d7 a5fe8f13 12a537ae 2f21364 200a9
Fuz2 many fac882b8 03eea34f bd792c40 2fe6fd54 2f21364 72816
That example was received by a DCC server with server-ID 1601 at about
8:25 GMT on the evening of February 7, 2000. The report was about a mail
message set to 5 addressees. The report was from a client that presented
a client-ID and matching password that the server recognized or authenti-
cated. The report was then sent or `flooded' to the server with server-
ID 101 which in turn sent it to a server with server-ID 103. That server
sent it to the local DCC server. The record is at the address 0x2fe5b94
in the database. The record contains 3 checksums. The simple checksum
of the body of the message was e2d3f96a c65aea01 3fece361 edff9ecf The
total number of recipients of messages with this body checksum known in
the database is 6, which implies this checksum had been previously
reported with a target count of 1. The previous report in the database
of a message with this body checksum is at 0x2f21364. The hash table
entry for this body checksum is at 0x772d2. This report included two
fuzzy checksums. Both have been previously reported as having been sent
to many targets.
An asterisk (*) before the name of the checksum would indicate that a
later record in the database makes this checksum redundant. A report of
many addressees makes all preceding reports redundant.
The string trimmed after the server-ID marks older reports that have had
uninteresting checksums removed. The string compressed after the server-
ID would indicate that this older report has been trimmed and compressed
with older reports.
With two -v arguments, records added to the database by dbclean(8) from
the server whitelist are also displayed.
Three -v arguments cause the hash table to be displayed. Three typical
hash table entries look like:
19b8: 19ee 19b7
19b9: 19c0 0 90120 Fuz1
19ba: 0 0 1b72300 Fuz1
The entry in slot number 0x19b8 is unused or free. Slot number 0x19b9 is
the start of a chain of collisions or entries with the same hash value of
0x19b9. The next slot in this chain is at 0x19c0. The corresponding
checksum is at 0x9012 in the database. The third slot at 0x19ba is also
that of a Fuz1 checksum, but it is not part of a hash chain and its data-
base record is at 0x1b72300.
/var/dcc is the DCC home directory containing data and control files.
main file of checksums.
database hash table.
memory mapped flooding positions.
cdcc(8), dcc(8), dbclean(8), dccd(8), dccifd(8), dccm(8), dccproc(8).
Implementation of dblist was started at Rhyolite Software in 2000. This
describes version 1.2.74.
FreeBSD 4.9 March 20, 2005 FreeBSD 4.9
Man(1) output converted with
modified for the DCC $Date 2001/04/29 03:22:18 $