.\" btest-rs manual page
.\" Generated for btest-rs v0.6.0
.TH BTEST 1 "2026-03-31" "btest-rs 0.5.0" "User Commands"
.SH NAME
btest \- MikroTik Bandwidth Test server and client
.SH SYNOPSIS
.B btest
.B \-s
.RI [ OPTIONS ]
.br
.B btest
.B \-c
.I HOST
.RB { \-t | \-r }
.RI [ OPTIONS ]
.SH DESCRIPTION
.B btest
is a Rust reimplementation of the MikroTik Bandwidth Test (btest) protocol.
It can operate as a server (accepting connections from MikroTik RouterOS
devices or other btest clients) or as a client (connecting to a MikroTik
device's built-in bandwidth test server).
.PP
The server listens on TCP port 2000 by default. MikroTik devices connect
to this port for handshake, authentication, and status exchange. UDP data
transfer uses ports 2001 and above.
.PP
Both MD5 challenge-response (RouterOS < 6.43) and EC-SRP5 Curve25519
(RouterOS >= 6.43) authentication are supported.
.SH OPTIONS
.SS "Mode Selection"
.TP
.BR \-s ", " \-\-server
Run in server mode. Listen for incoming connections from MikroTik devices
or other btest clients. Conflicts with
.BR \-c .
.TP
.BI \-c " HOST" "\fR, \fP" \-\-client " HOST"
Run in client mode, connecting to the specified
.IR HOST .
The host can be an IPv4 address, IPv6 address, or hostname. Conflicts with
.BR \-s .
.SS "Test Direction (client mode)"
.TP
.BR \-t ", " \-\-transmit
Client transmits data to the server (upload test). Can be combined with
.B \-r
for bidirectional testing.
.TP
.BR \-r ", " \-\-receive
Client receives data from the server (download test). Can be combined with
.B \-t
for bidirectional testing.
.SS "Protocol and Transfer"
.TP
.BR \-u ", " \-\-udp
Use UDP instead of TCP for data transfer. UDP uses separate data ports
(2001+ server side, 2257+ client side) and exchanges status messages
over the TCP control channel every second.
.TP
.BI \-b " BW" "\fR, \fP" \-\-bandwidth " BW"
Target bandwidth limit for the test. Accepts suffixes:
.B K
(kilobits/sec),
.B M
(megabits/sec),
.B G
(gigabits/sec). Examples:
.BR 100M ", " 1G ", " 500K .
Default is 0 (unlimited).
.TP
.BI \-P " PORT" "\fR, \fP" \-\-port " PORT"
TCP port to listen on in server mode or connect to in client mode.
Default: 2000.
.SS "Network Binding (server mode)"
.TP
.BI \-\-listen " ADDR"
IPv4 address to bind the server listener to. Use
.B none
to disable IPv4 listening entirely (useful with
.B \-\-listen6
for IPv6-only mode). Default: 0.0.0.0.
.TP
.BI \-\-listen6 " \fR[\fPADDR\fR]\fP"
Enable the IPv6 listener. If no address is given, binds to
.BR :: .
Experimental: TCP over IPv6 works fully on all platforms. UDP over IPv6
has issues on macOS due to kernel ENOBUFS limitations. On Linux, IPv6 UDP
works correctly.
.SS "Authentication"
.TP
.BI \-a " USER" "\fR, \fP" \-\-authuser " USER"
Authentication username. In server mode, connecting clients must provide
this username. In client mode, this username is sent to the server.
.TP
.BI \-p " PASS" "\fR, \fP" \-\-authpass " PASS"
Authentication password. In server mode, connecting clients must provide
a matching password. In client mode, this password is used to authenticate
with the server.
.TP
.B \-\-ecsrp5
Use EC-SRP5 authentication (Curve25519 Weierstrass). In server mode, this
causes the server to advertise EC-SRP5 instead of MD5 to connecting clients.
Required for RouterOS >= 6.43 devices. In client mode, the authentication
type is auto-detected from the server's response and this flag is not needed.
.SS "Test Control"
.TP
.BI \-d " SECS" "\fR, \fP" \-\-duration " SECS"
Test duration in seconds (client mode only). The client exits cleanly after
the specified number of seconds. A value of 0 means unlimited (run until
interrupted with Ctrl-C). Default: 0.
.TP
.BR \-n ", " \-\-nat
NAT traversal mode. Sends an empty UDP probe packet to the server before
starting the receive thread, opening a hole in NAT firewalls. Only relevant
for UDP receive tests when the client is behind NAT.
.SS "Logging and Output"
.TP
.BI \-\-csv " FILE"
Output test results to a CSV file. Appends a row for each completed test.
Creates the file with a header row if it does not exist. Columns:
timestamp, host, port, protocol, direction, duration_s, tx_avg_mbps,
rx_avg_mbps, tx_bytes, rx_bytes, lost_packets, auth_type.
.TP
.BR \-q ", " \-\-quiet
Suppress per-second bandwidth output to the terminal. Useful in combination
with
.B \-\-csv
for machine-readable-only output, or when running as a background service.
.TP
.BI \-\-syslog " HOST:PORT"
Send structured log events to a remote syslog server via UDP. Uses RFC 3164
(BSD syslog) format with facility local0. Events include AUTH_SUCCESS,
AUTH_FAILURE, TEST_START, and TEST_END with detailed metadata.
Example:
.BR \-\-syslog\ 192.168.1.1:514 .
.TP
.BR \-v ", " \-\-verbose
Increase log verbosity. Can be repeated for more detail:
.RS
.TP
.B \-v
Debug messages (connection lifecycle, authentication steps).
.TP
.B \-vv
Trace messages (hex dumps of protocol exchange).
.TP
.B \-vvv
Maximum verbosity.
.RE
.TP
.BR \-h ", " \-\-help
Print help information and exit.
.TP
.BR \-V ", " \-\-version
Print version information and exit.
.SH EXAMPLES
.SS "Server Mode"
Start a basic server with no authentication:
.PP
.RS
.nf
btest -s
.fi
.RE
.PP
Server with MD5 authentication:
.PP
.RS
.nf
btest -s -a admin -p password
.fi
.RE
.PP
Server with EC-SRP5 authentication (RouterOS >= 6.43):
.PP
.RS
.nf
btest -s -a admin -p password --ecsrp5
.fi
.RE
.PP
Server with syslog and CSV logging:
.PP
.RS
.nf
btest -s -a admin -p password --syslog 10.0.0.1:514 --csv /var/log/btest.csv
.fi
.RE
.PP
Server listening on IPv4 and IPv6:
.PP
.RS
.nf
btest -s --listen6
.fi
.RE
.PP
Server on a custom port with debug output:
.PP
.RS
.nf
btest -s -P 3000 -v
.fi
.RE
.SS "Client Mode"
TCP download test:
.PP
.RS
.nf
btest -c 192.168.88.1 -r
.fi
.RE
.PP
TCP upload test:
.PP
.RS
.nf
btest -c 192.168.88.1 -t
.fi
.RE
.PP
Bidirectional TCP test:
.PP
.RS
.nf
btest -c 192.168.88.1 -t -r
.fi
.RE
.PP
UDP download test:
.PP
.RS
.nf
btest -c 192.168.88.1 -r -u
.fi
.RE
.PP
UDP bidirectional with bandwidth limit:
.PP
.RS
.nf
btest -c 192.168.88.1 -t -r -u -b 100M
.fi
.RE
.PP
Timed test (30 seconds) with CSV output:
.PP
.RS
.nf
btest -c 192.168.88.1 -r -d 30 --csv results.csv
.fi
.RE
.PP
Quiet mode with CSV only:
.PP
.RS
.nf
btest -c 192.168.88.1 -r -d 60 --csv results.csv -q
.fi
.RE
.PP
With authentication:
.PP
.RS
.nf
btest -c 192.168.88.1 -r -a admin -p password
.fi
.RE
.PP
UDP receive through NAT:
.PP
.RS
.nf
btest -c 192.168.88.1 -r -u -n
.fi
.RE
.SH PORTS
.TP
.B 2000/tcp
Control channel. Used for handshake, authentication, and status exchange.
.TP
.B 2001-2100/udp
Server-side UDP data ports. Each connection uses the next available port
starting from 2001.
.TP
.B 2257-2356/udp
Client-side UDP data ports. Offset from server port by 256.
.SH EXIT STATUS
.TP
.B 0
Success. The test completed normally or the duration expired.
.TP
.B 1
Error. Failed to connect, authentication failed, or invalid arguments.
.SH ENVIRONMENT
.TP
.B RUST_LOG
Override the log filter. When set, takes precedence over the
.B \-v
flag. Example:
.BR RUST_LOG=trace .
.SH FILES
.TP
.I /usr/local/bin/btest
Default installation path for the binary.
.TP
.I /etc/systemd/system/btest.service
systemd unit file created by the install-service.sh script.
.SH AUTHENTICATION
.B btest
supports two authentication schemes:
.TP
.B MD5 (legacy)
Double MD5 challenge-response. Compatible with RouterOS versions before 6.43.
The server sends a 16-byte random challenge. The client responds with
MD5(password + MD5(password + challenge)) and the username.
.TP
.B EC-SRP5 (modern)
Elliptic Curve Secure Remote Password using Curve25519 in Weierstrass form.
Used by RouterOS >= 6.43. Provides zero-knowledge password proof. Enable on
the server with
.BR \-\-ecsrp5 .
Clients auto-detect the authentication type.
.SH MIKROTIK CONFIGURATION
Enable the bandwidth test server on MikroTik for client mode:
.PP
.RS
.nf
/tool/bandwidth-server set enabled=yes
.fi
.RE
.PP
Run a test from MikroTik connecting to a btest-rs server:
.PP
.RS
.nf
/tool/bandwidth-test address=<server-ip> direction=both \\
    protocol=udp user=admin password=password
.fi
.RE
.SH SEE ALSO
.BR iperf3 (1),
.BR netperf (1)
.PP
Project documentation:
.I https://github.com/samm-git/btest-opensource
.SH CREDITS
.B btest-opensource
by Alex Samorukov \(em original C implementation and protocol
reverse-engineering (MIT License).
.PP
.B Margin Research
\(em EC-SRP5 authentication reverse-engineering for MikroTik RouterOS
(Apache License 2.0).
.PP
.B MikroTik
\(em creator of the bandwidth test protocol and RouterOS.
.SH LICENSE
MIT License. See the LICENSE file in the source distribution.
.PP
This project is derived from btest-opensource (MIT License, Copyright 2016
Alex Samorukov). The EC-SRP5 implementation is based on research by Margin
Research (Apache License 2.0).
.SH AUTHORS
btest-rs contributors.