Provided by: ipac-ng_1.31-1ubuntu3_i386
fetchipac - ip accounting kernel data and database handler
fetchipac [ -b|--batch ] [ -d|--directory DIR ] [ -h|--help ] [
-m|--machine-output-format ] [ -r|--records ] [ -R|--list-raw ] [
-s|--storage-method METHOD ] [ -S|--start ] [ -t|--timestamps
[START][,END] ] [ -v|--verbose ]
fetchipac is part of the ipac-ng linux ip accounting package.
fetchipac reads the kernel ip counters and stores this information in a
database. It also provides access to the database for other programs,
mainly for ipacsum(8).
If you are an average user of ipac, you don’t want to know about most
of the things described here. You will want to run fetchipac regulary
from cron, probably without any options. You will possibly want to use
the options --directory and --storage-method. The rest is mostly for
internal use by ipac and for debugging the database.
fetchipac operates in different modes and does fairly unrelated things.
The only common thing it does is that it accesses a database. The
database can be of different types which are called storage methods.
The storage methods provided are: gdbm plain-file . The default
storage method used is plain-file. fetchipac uses a directory to store
data. The default directory for that is /var/lib/ipac. If the storage
method does not make use of this directory, for example, if it stores
the data on a remote host, the directory is still used for the spool
file (see below). (All these defaults are determined at build time and
this man page is updated automatically.)
When fetchipac is called without any arguments, it fetches kernel ip
To do this, it first runs through a lock mechanism to prevent multiple
instances of fetchipac to run at the same time. Then, it reads the ipac
rule file, /var/run/ipac.rules, which maps kernel ip accounting data to
names. Next, it reads the kernel ip accounting data from the
appropriate file in /proc/net, which is /proc/net/ip_fwchains if you
have an ipchains system (kernel 2.1.* or newer) fetchipac opens this
file in read/write mode; this makes the kernel set all counters to zero
in the moment the file is opened and we can be sure to count every byte
only once (see BUGS section. In case of kernel 2.4.* it uses kernel’s
internal structures to read byte and packet counters.
After reading and closing those files, fetchipac creates a new record
in its database using the default storage method.
There is a spool mechanism which allows fetchiapc to spool ip
accounting data in a file when the database cannot be opened. For
example, if the storage method stores data on a remote host, the remote
host might be down or unreachable. Another example is the gdbm storage
method; if some other process accesses a gdbm file, it is locked and
can’t be written to. If fetchipac could not spool the data, it would
be lost in either case.
If the database can’t be opened, the data collected from the kernel is
put into a spool file. The spool file resides in the data directory and
its name is spool. If there is already data in this spool file, the
new records are appended. The data is stored in this file in the same
format as described unter the batch mode command ADD (see below).
Whenever fetchipac runs, it checks if the spool file exists. If so, and
if the database can be opened, the contents of the spool file is copied
into the database and the spool file is removed.
Use a different data directory DIR instead of the default,
/var/lib/ipac, for the database (if the storage method uses a
directory to store data) and the spool file.
Print a help message and exit.
Use METHOD as the storage method. METHOD can be one of the
compiled in storage methods. Run fetchipac --help to see which
storage methods exactly have been compiled in.
initial accounting setup: insert accounting rules and chains
according to your /etc/ipac-ng/ipac.conf
OPTIONS USED INTERNALLY AND FOR DEBUGGING
Switch to batch mode. In this mode, fetchipac does not fetch ip
accounting data from the kernel. Instead, it displays a prompt,
"> ", on standard output and then expects commands. fetchipac
exists when the command QUIT was entered or at end of file on
stdin. See below, section BATCH MODE, for a description of the
When using the --record or --timestamps options, fetchipac
normally prints the data in a nice human readable format. When
using this option, the data will be formatted in a way that it
is easily parsable by a program. This is used by ipacsum(8).
When used with --record, the output generated will be in the
format fetchipac expects in batch mode with the ADD command.
When used with --timestamps, the output generated will be in the
format expected on standard input with the --record option.
Switch to record retrieve mode. In this mode, fetchipac does not
read the kernel ip accounting data from the kernel. Instead, it
reads lines from standard input and exits on end of file on
stdin. The lines are interpreted as decimal numbers which
represent timestamps. (The lines may begin with a single
character ’+’, ’-’ or ’*’, which is discarded. The number may
also be preceded by white spaces.)
For every timestamp read, fetchipac tries to retrieve the record
from the database. If such a record is not found, it prints
"ERROR". If it is found, the record is displayed in a human
readable format. (See also option --machine-output-format.)
List rules and chains to be inserted into firewall. Don’t
actually insert them, just list.
Print all timestamps for which there are records in the
database. If given, start with timestamp START and end with END.
START is interpreted exclusively (if a timestamp START exists,
it will NOT be printed) and END is interpreted inclusively (if a
timestamp END exists, it WILL be printed).
Also, print the final timestamp before START and the first
timestamp after END.
The output will be in a human readable format, unless the
--machine-output-format option is given.
Be verbose. Add more ’v’ for more verbosity.
When fetchipac is in batch mode (option --batch), it recognizes the
following commands on standard input:
ADD The ADD command is used to add a record to the database. The ADD
command takes no arguments, but after giving the ADD command,
fetchipac expects one data record on standard input.
The data record consists of a decimal number representing the
timestamp of the record, followed by a space character, followed
by a decimal number representing the number of sub records that
will follow, followed by a newline character, followed by the
individual sub records, followed by a newline character.
A sub record consists of the character ’(’, followed by a space
character, followed by a host name representing the machine
where the data was measured, followed by a newline character,
followed by individual rules, followed by the character ’)’,
followed by a newline character.
A rule consists of a decimal number representing a byte count,
followed by a space character, followed by a decimal number
representing a packet count, followed by a space character,
followed by the character ’|’, followed by a rule name, followed
by the character ’|’, followed by a newline character.
The ADD command format data can be created using the --records
and --machine-output-format options of fetchipac (together).
Note: The whole record is terminated by an empty line. If there
is only one sub record, the whole thing end with a line with
only a ’)’ followed by an empty line.
The DELETE command takes exactly one arguement: A timestamp (a
decimal number). fetchpipac tries to delete the record with
this timestamp from the database. If there is no such record, it
prints "ERROR"; otherwise, the deletion is performed and the
prompt is displayed again.
LIST START END
START and END are two parameters: Dicimal numbers, representing
two timestamps. The operation performed is the same as with the
option --timstamps, so see there.
The ipac configuration file.
ip accounting rule name file.
The spool file.
Warning: ipac chains and/or jumps are corrupted. Trying to fix them
Some program or human deleted one of ipac’s chains or jump
rules. This probably means that no traffic was counted by ipac
since the deletion. It may be caused by firewall set up
scripts. For example, performing ipchains --flush or -F has this
effect. fetchipac automatically runs ipacset --fix-chains to
fix this condition. See ipacset(8), section BUGS, for details.
Sorry, this section is obsolete and needs to be rewritten, just
do fetchipac -S
no ip firewall / accounting code in the kernel
The kernel had been compiled without the ip accounting feature.
many more messages
Which are meant to speak for themselves.
Resetting accounting data counters on ipchains systems resets all
counters; there is no way to reset only ipac’s counters. Thus, you
probably can’t use other ip accounting software together which ipac on
the same system. This is not right under iptables system. Also, there
are some things (bugs) in ipchains from 2.4.* kernels and using it is
no good. (shortly: dont even try to use ipchains with 2.4.* kernels!)
This man page belongs to ipac-ng version 1.31. For updates and other
information, look at http://sf.net/projects/ipac-ng
fetchipac is part of ipac since the beginning. It started as a kernel
data fetch program only. Until February 2000, it has been a shell
script and was then rewritten in C. For ipac 2, it grew a lot, because
database access funtions were added and it became the database access
program ipacsum(8) uses.
Moritz Both <email@example.com>
Al Zaharov <firstname.lastname@example.org>