bro man page

bro — passive network traffic analyzer

Synopsis

bro [options] [file ...]

Description

Bro is primarily a security monitor that inspects all traffic on a link in depth for signs of suspicious activity. More generally, however, Bro supports a wide range of traffic analysis tasks even outside of the security domain, including performance measurements and helping with trouble-shooting.

Bro comes with built-in functionality for a range of analysis and detection tasks, including detecting malware by interfacing to external registries, reporting vulnerable versions of software seen on the network, identifying popular web applications, detecting SSH brute-forcing, validating SSL certificate chains, among others.

Options

<file>
policy file, or read stdin
-a--parse-only
exit immediately after parsing scripts
-b--bare-mode
don't load scripts from the base/ directory
-d--debug-policy
activate policy file debugging
-e--exec <bro code>
augment loaded policies by given code
-f--filter <filter>
tcpdump filter
-g--dump-config
dump current config into .state dir
-h--help|-?
command line help
-i--iface <interface>
read from given interface
-p--prefix <prefix>
add given prefix to policy file resolution
-r--readfile <readfile>
read from given tcpdump file
-s--rulefile <rulefile>
read rules from given file
-t--tracefile <tracefile>
activate execution tracing
-w--writefile <writefile>
write to given tcpdump file
-v--version
print version and exit
-x--print-state <file.bst>
print contents of state file
-z--analyze <analysis>
run the specified policy file analysis
-C--no-checksums
ignore checksums
-F--force-dns
force DNS
-I--print-id <ID name>
print out given ID
-J--set-seed <seed>
set the random number seed
-K--md5-hashkey <hashkey>
set key for MD5-keyed hashing
-N--print-plugins
print available plugins and exit (-NN for verbose)
-P--prime-dns
prime DNS
-Q--time
print execution time summary to stderr
-R--replay <events.bst>
replay events
-S--debug-rules
enable rule debugging
-T--re-level <level>
set 'RE_level' for rules
-U--status-file <file>
Record process status in file
-W--watchdog
activate watchdog timer
-X--broxygen <cfgfile>
generate documentation based on config file
--pseudo-realtime[=<speedup>]
enable pseudo-realtime for performance evaluation (default 1)
--load-seeds <file>
load seeds from given file
--save-seeds <file>
save seeds to given file
The following option is available only when Bro is built with the --enable-debug configure option:
-B--debug <dbgstreams>
Enable debugging output for selected streams ('-B help' for help)
The following options are available only when Bro is built with gperftools support (use the --enable-perftools and --enable-perftools-debug configure options):
-m--mem-leaks
show leaks
-M--mem-profile
record heap

Environment

BROPATH
file search path
BRO_PLUGIN_PATH
plugin search path
BRO_PLUGIN_ACTIVATE
plugins to always activate
BRO_PREFIXES
prefix list
BRO_DNS_FAKE
disable DNS lookups
BRO_SEED_FILE
file to load seeds from
BRO_LOG_SUFFIX
ASCII log file extension
BRO_PROFILER_FILE
Output file for script execution statistics
BRO_DISABLE_BROXYGEN
Disable Broxygen documentation support

Author

bro was written by The Bro Project <info@bro.org>.

Info

November 2014 bro System Administration Utilities