Provided by: bwctl-server_1.5.4+dfsg1-1build1_amd64 
NAME
bwctld.conf - Bandwidth Control daemon configuration file
DESCRIPTION
The bwctld.conf file is the configuration file for the bwctld(8) program. It is used to configure the
basic operation of the server. For example, what addresses and ports it should listen on, where it should
send error messages, and where it should save files.
The policy rules for bwctld are configured using the bwctld.limits file; the details for configuring
those policies are described in the bwctld.limits(5) manual page.
The format of this file is:
• Comment lines are any line where the first non-whitespace character is '#'. These lines
are counted for the purposes of returning line numbers in error messages but are otherwise
ignored by the spawned bwctld.
• Lines may be continued using the semi-standard '\' character followed immediately by a
newline character. This is the only valid place for the '\' character. If it is found
elsewhere, a syntax error is reported.
• Blank lines are treated as comment lines.
• All other lines are used to set configuration options. The format of these lines is an
initial keyword followed by a variable list of arguments, separated by whitespace.
CONFIGURATION OPTIONS
access_priority priority
Syslog priority to log access messages.
Default:
LOG_INFO
allow_unsync
Directs bwctld to continue accepting valid requests for throughput tests when the system clock is
not synchronized. bwctld prefers to have an NTP synchronized system clock to ensure the two
endpoints of the test are actually agreeing to the same scheduled time window for test execution.
This option is used to bypass this requirement for systems that either do not have the NTP system
calls, or prefer not to configure NTP.
Note: if the difference between the system clocks on the two endpoints is too great, the eventual
throughput test will fail when the endpoints attempt to run the test at different times. The
threshold for this difference is controlled using the sync_fuzz option. (If you set allow_unsync,
you should set sync_fuzz to a reasonable value for your system.)
Default:
unset (set if the operating system does have the NTP system calls)
auth_mode authmode
Specify the authentication modes the server is willing to use for communication. auth_mode should
be set as a character string, with any or all of the characters "AEO". The modes are:
A [A]uthenticated. This mode encrypts the control connection.
E [E]ncrypted. This mode encrypts the control connection. If the test supports encryption,
this mode will additionally encrypt the test stream. (Encryption of the test stream is not
currently supported, so this mode is currently identical to authenticated.)
O [O]pen. No encryption of any kind is done.
The server can specify all the modes with which it is willing to communicate. The most strict mode
that both the server and the client are willing to use will be selected.
Default:
"AEO"
bottleneck_capacity bottleneckcapacity
This value is used in the algorithm to dynamically set the TCP send/recv window sizes. This option
is likely to be removed in the future once a dynamic bottleneck_capacity algorithm is incorporated
into the code. (This option only really works when the local NIC is the bottleneck.) If this
option is not specified, the dynamic window calculation requested by the -W option to bwctl is not
done and the advisory value is used.
Default:
unset
control_timeout controltimeout
Number of seconds to wait for protocol messages before timing out. This value should be
significantly larger than what typical users specify for the -I flag of bwctl or bwctl will have
to open a new control connection for each new test it requests.
Default:
7200 (Picked to be the same as the default for TCP keepalive)
die_by dieby
Number of seconds to wait for child processes to gracefully terminate before killing them with
SIGKILL. This is in response to the master process receiving SIGTERM or SIGHUP.
Default:
5
disable_iperf
Prevent bwctl from executing Iperf tests
Default:
unset
disable_iperf3
Prevent bwctl from executing Iperf3 tests
Default:
unset
disable_nuttcp
Prevent bwctl from executing Nuttcp tests
Default:
unset
disable_owamp
Prevent bwctl from executing Owamp tests
Default:
unset
disable_ping
Prevent bwctl from executing Ping tests
Default:
unset
disable_tracepath
Prevent bwctl from executing Tracepath tests
Default:
unset
disable_traceroute
Prevent bwctl from executing Traceroute tests
Default:
unset
facility facility
Syslog facility to log messages.
Default:
LOG_DAEMON
group group
Specifies the gid the bwctld process should run as. group can be specified using a valid group
name on the system or by using -gid. This option is only used if bwctld is started as root.
Default:
unset
iperf_cmd iperfcmd
The path to the Iperf command on the system. If the iperf_cmd does not contain a '/' character,
then the PATH of the bwctld environment will be searched to find the Iperf executable.
Default:
iperf
iperf_port iperfport
The port number(s) that Iperf receivers will use. Currently, bwctld simply cycles through this
range linearly. iperf_port can be specified as a single valid port number or as a range as
low-high. The range must be specified as two valid port numbers with the '-' character separating
them. Whitespace is not allowed within the iperf_port. For example, "5001-5004" would be valid,
but "5001 - 5004" would be invalid.
This value should be set to a range because it can take a few minutes for a port to become free
after a test has run. If the port is not free when the next test starts, the test will fail. If
set to a range, the daemon will cycle through them when starting tests, decreasing the chance that
a port will still be open when the test starts. For best results, ensure that this range is
different from that of nuttcp_port and thrulay_port.
Default:
unset
iperf3_port iperf3port
The port number(s) that Iperf3 receivers will use. Currently, bwctld simply cycles through this
range linearly. iperf3_port can be specified as a single valid port number or as a range as
low-high. The range must be specified as two valid port numbers with the '-' character separating
them. Whitespace is not allowed within the iperf3_port. For example, "5001-5004" would be valid,
but "5001 - 5004" would be invalid.
This value should be set to a range because it can take a few minutes for a port to become free
after a test has run. If the port is not free when the next test starts, the test will fail. If
set to a range, the daemon will cycle through them when starting tests, decreasing the chance that
a port will still be open when the test starts. For best results, ensure that this range is
different from that of nuttcp_port and thrulay_port.
Default:
unset
log_location
Directs the bwctld process to report source code file and line number information with error
messages. This is a particularly useful option to set when sending in messages as part of a bug
report.
Default:
unset
nuttcp_cmd nuttcpcmd
The path to the Nuttcp command on the system. If the nuttcp_cmd does not contain a '/' character,
then the PATH of the bwctl environment will be searched to find the Nuttcp executable.
Default:
nuttcp
nuttcp_port nuttcpport
The port number(s) that Nuttcp receivers will use. Currently, bwctld simply cycles through this
range linearly. nuttcp_port can be specified as a single valid port number or as a range as
low-high. The range must be specified as two valid port numbers with the '-' character separating
them. Whitespace is not allowed within the nuttcp_port. For example, "5001-5004" would be valid,
but "5001 - 5004" would be invalid.
This value should be set to a range because it can take a few minutes for a port to become free
after a test has run. If the port is not free when the next test starts, the test will fail. If
set to a range, the daemon will cycle through them when starting tests, decreasing the chance that
a port will still be open when the test starts. For best results, ensure that this range is
different from that of iperf_port and thrulay_port.
Default:
unset
owamp_cmd owampcmd
The path to the owping command on the system. If the owamp_cmd does not contain a '/' character,
then the PATH of the bwctl environment will be searched to find the owping executable.
Default:
owping
owamp_server_cmd owampservercmd
The path to the owampd command on the system. If the owamp_server_cmd does not contain a '/'
character, then the PATH of the bwctl environment will be searched to find the owampd executable.
Default:
owampd
owamp_port owampport
The port number(s) that Owamp receivers will use. Currently, bwctld simply cycles through this
range linearly. owamp_port must be specified as a range as low-high. The range must be specified
as two valid port numbers with the '-' character separating them. Whitespace is not allowed within
the owamp_port. For example, "5001-5004" would be valid, but "5001 - 5004" would be invalid.
This value must be set to a range because it is used for both the Owamp communication and test
ports.
Default:
unset
peer_port 0 | lowport-highport
Specify the port range that will be used on the local host for peer connections to other bwctld
servers. These connections are used to verify clock timing between the servers and to exchange
test results. This is a required part of the protocol used by BWCTL to run tests. However, this
option allows system administrators to limit these connections to a specific port range, which
should allow BWCTL to work in a firewall environment. This option can be specified in two ways.
First, as a 0, which would indicate that bwctld should allow the system to pick the port
(ephemeral). Second, as a range. lowport must be a smaller value than highport and both numbers
must be valid port values. (16-bit unsigned integer values)
Default:
0
ping_cmd pingcmd
The path to the ping command on the system. If the ping_cmd does not contain a '/' character, then
the PATH of the bwctl environment will be searched to find the ping executable.
Default:
ping
ping6_cmd ping6cmd
The path to the ping6 command on the system. If the ping6_cmd does not contain a '/' character,
then the PATH of the bwctl environment will be searched to find the ping6 executable.
Default:
ping6
post_hook /path/to/script
Specifies a script to run after each bwctl session has finished. These hooks can be used to save
the results into a database, track usage or any number of other tasks. You can specify as many
hooks as you want by including multiple post_hook entries.
priority priority
Syslog priority to log error messages.
Default:
LOG_ERR
root_folly
Disables the checks that disable bwctld if it is run with root permissions. There are legitimate
reasons to run bwctld as root, but it is risky. Forcing this additional option will make it less
likely root permissions are accidently used.
Default:
unset
src_node nodename:port
Specify the address and port on which bwctld will listen for requests. nodename can be specified
using a DNS name or using the textual representation of the address. It is possible to set the
source address without setting the port by simply leaving off the ':' and port specification. If
an IPv6 address is specified, note that the accepted format contains nodename in square brackets
as: [fe80::fe9f:62d8]. This ensures the port number is distinct from the address specification.
Default:
nodename is wildcarded as any currently available address
port is 4823
sync_fuzz syncfuzz
This value is added to the NTP error estimates to increase the tolerance of bwctld to incomplete
NTP configurations, or if the NTP system calls are not available. If NTP is unavailable to bwctld
it assumes the clock is accurate to within one second plus the value of sync_fuzz. This option is
specified as a floating point number in seconds. For example, to indicate that the system is
synchronized within one second, you could specify this option as 1.0.
Practically, this option is used to determine the size of the time window buffer before and after
each throughput test.
Default:
0.0
test_port testport
The port number(s) that receivers of all test types will use, unless otherwise set using one of
the other port variables. Currently, bwctld simply cycles through this range linearly. test_port
must be specified as a range as low-high. The range must be specified as two valid port numbers
with the '-' character separating them. Whitespace is not allowed within the test_port. For
example, "5001-5004" would be valid, but "5001 - 5004" would be invalid.
This value must be set to a range because it is used for both the Owamp communication and test
ports.
Default:
5001-5900
thrulay_port thrulayport
The port number(s) that Thrulay receivers will use. Currently, bwctld simply cycles through this
range linearly. thrulay_port can be specified as a single valid port number or as a range as
low-high. The range must be specified as two valid port numbers with the '-' character separating
them. Whitespace is not allowed within the thrulay_port. For example, "5001-5004" would be valid,
but "5001 - 5004" would be invalid.
This value should be set to a range because it can take a few minutes for a port to become free
after a test has run. If the port is not free when the next test starts, the test will fail. If
set to a range, the daemon will cycle through them when starting tests, decreasing the chance that
a port will still be open when the test starts. For best results, ensure that this range is
different from that of iperf_port and nuttcp_port.
Default:
unset
tracepath_cmd tracepathcmd
The path to the tracepath command on the system. If the tracepath_cmd does not contain a '/'
character, then the PATH of the bwctl environment will be searched to find the tracepath
executable.
Default:
tracepath
tracepath6_cmd tracepath6cmd
The path to the tracepath6 command on the system. If the tracepath6_cmd does not contain a '/'
character, then the PATH of the bwctl environment will be searched to find the tracepath6
executable.
Default:
tracepath6
traceroute_cmd traceroutecmd
The path to the traceroute command on the system. If the traceroute_cmd does not contain a '/'
character, then the PATH of the bwctl environment will be searched to find the traceroute
executable.
Default:
traceroute
traceroute6_cmd traceroute6cmd
The path to the traceroute6 command on the system. If the traceroute6_cmd does not contain a '/'
character, then the PATH of the bwctl environment will be searched to find the traceroute6
executable.
Default:
traceroute6
user user
Specifies the uid the bwctld process should run as. user can be specified using a valid user name
on the system or by using -uid. This option is only used if bwctld is started as root. If the
given user has root permissions, the root_folly option must also be specified.
Default:
unset
var_dir vardir
Directory path where the bwctld.pid file will be placed.
Default:
Current directory
SEE ALSO
bwctl(1), bwctld(8), bwctld.limits(5), bwctld.keys(5), and the http://software.internet2.edu/bwctl/ web
site.
For details on Iperf3, see the https://github.com/esnet/iperf web site.
For details on Iperf, see the http://sourceforge.net/projects/iperf web site.
For details on Nuttcp, see the http://www.wcisd.hpc.mil/nuttcp/Nuttcp-HOWTO.html web site.
For details on Owamp, see the http://software.internet2.edu/owamp web site.
ACKNOWLEDGMENTS
This material is based in part on work supported by the National Science Foundation (NSF) under Grant No.
ANI-0314723. Any opinions, findings, and conclusions or recommendations expressed in this material are
those of the author(s) and do not necessarily reflect the views of the NSF.
$Date: 2008-10-09 12:27:47 -0400 (Thu, 09 Oct 2008) $ bwctld.conf(5)