failure to generate alerts from tcpdump file

[jwang () fit edu]

hi, everyone:
I am all new to snort, and just finished install and configed the
snort.conf file, also downloaded and installed the latest ruleset from
snort.org. but when i was trying to do the following command, it failed!
if i take out "-c /.../snort.conf" in command line, the system will only
give me an empty alert file?! i would like to knw if there is more i have
to config, any other command that will give me the alerts that i wanted?

[root@localhost snort]# snort -s -r attack_file_8.tcpdump -c
/etc/snort/conf/rules -c /etc/snort/conf/snort.conf
...
Warning: /etc/snort/conf/rules/exploit.rules(42) => Unknown keyword
'isdataat' in rule!
Warning: /etc/snort/conf/rules/exploit.rules(42) => Unknown keyword 'pcre'
in rule!
Warning: /etc/snort/conf/rules/exploit.rules(44) => Unknown keyword
'isdataat' in rule!
Warning: /etc/snort/conf/rules/exploit.rules(44) => Unknown keyword 'pcre'
in rule!
Warning: /etc/snort/conf/rules/exploit.rules(46) => Unknown keyword 'pcre'
in rule!
Warning: /etc/snort/conf/rules/exploit.rules(47) => Unknown keyword 'pcre'
in rule!
ERROR: ERROR /etc/snort/conf/rules/exploit.rules (49): Bad arguments to
byte_test: 2,30
Fatal Error, Quitting..

thanks a lot, any tips will useful!

jun Wang (jwang () fit edu)


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