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denyhosts(8) [centos man page]

DENYHOSTS(8)							   User Commands						      DENYHOSTS(8)

DenyHosts - version: 2.6 DESCRIPTION
DenyHosts is a python program that automatically blocks ssh attacks by adding entries to /etc/hosts.deny. DenyHosts will also inform Linux administrators about offending hosts, attacked users and suspicious logins. Usage: /usr/sbin/denyhosts [-f logfile | --file=logfile] [ -c configfile | --config=configfile] [-i | --ignore] [-n | --noemail] [--purge] [--migrate] [--daemon] [--sync] [--version] --file: The name of log file to parse --ignore: Ignore last processed offset (start processing from beginning) --noemail: Do not send an email report --unlock: if lockfile exists, remove it and run as normal --migrate: migrate your HOSTS_DENY file so that it is suitable for --purge --purge: expire entries older than your PURGE_DENY setting --daemon: run DenyHosts in daemon mode --foreground: run DenyHosts in foreground mode --sync: run DenyHosts synchronization mode --version: Prints the version of DenyHosts and exits Note: multiple --file args can be processed. If multiple files are provided, --ignore is implied Note: in a debian system, the default running mode is daemon mode and the configuration file is etc/denyhosts.conf When run in --daemon mode the following flags are ignored: --file, --purge, --migrate, --sync, --verbose SEE ALSO
Please refer to for full documentation This file can be also found in /usr/share/doc/deny- hosts/FAQ.html AUTHOR
DenyHosts was written by Phil Schwartz <> This manual page was written by Marco Bertorello <> for the Debian project (but may be used by others). DenyHosts version: 2.6 July 2006 DENYHOSTS(8)

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PORTSENTRY(8)						      System Manager's Manual						     PORTSENTRY(8)

portsentry - detect portscan activity SYNOPSIS
portsentry [ -tcp | -stcp | -atcp ] portsentry [ -udp | -sudp | -audp ] DESCRIPTION
This manual page documents briefly the portsentry command. This manual page was written for the Debian GNU/Linux distribution because the original program does not have a manual page. portsentry is a program that tries to detect portscans on network interfaces with the ability to detect stealth scans. On alarm portsentry can block the scanning machine via hosts.deny (see hosts_access(5), firewall rule (see ipfwadm(8), ipchains(8) and iptables(8)) or dropped route (see route(8)). OPTIONS
For details on the various modes see /usr/share/doc/portsentry/README.install -tcp tcp portscan detection on ports specified under TCP_PORTS in the config file /etc/portsentry/portsentry.conf. -stcp As above but additionally detect stealth scans. -atcp Advanced tcp or inverse mode. Portsentry binds to all unused ports below ADVANCED_PORTS_TCP given in the config file /etc/portsen- try/portsentry.conf. -udp udp portscan detection on ports specified under UDP_PORTS in the config file /etc/portsentry/portsentry.conf. -sudp As above but additionally detect "stealth" scans. -audp Advanced udp or inverse mode. Portsentry binds to all unused ports below ADVANCED_PORTS_UDP given in the config file /etc/portsen- try/portsentry.conf. CONFIGURATION FILES
portsentry keeps all its configuration files in /etc/portsentry. portsentry.conf is portsentry's main configuration file. See portsen- try.conf(5) for details. The file portsentry.ignore contains a list of all hosts that are ignored, if they connect to a tripwired port. It should contain at least the localhost(, and the IP addresses of all local interfaces. You can ignore whole subnets by using a notation <IP Address>/<Netmask Bits>. It is *not* recommend putting in every machine IP on your network. It may be important for you to see who is con- necting to you, even if it is a "friendly" machine. This can help you detect internal host compromises faster. If you use the /etc/init.d/portsentry script to start the daemon, portsentry.ignore is rebuild on each start of the daemon using portsen- try.ignore.static and all the IP addresses found on the machine via ifconfig. /etc/default/portsentry specifies in which protocol modes portsentry should be startet from /etc/init.d/portsentry There are currently two options: TCP_MODE= either tcp, stcp or atcp (see OPTIONS above). UDP_MODE= either udp, sudp or audp (see OPTIONS above). The options above correspond to portsentry's commandline arguments. For example TCP_MODE="atcp" has the same effect as to start portsentry using portsentry -atcp. Only one mode per protocol can be started at a time (i.e. one tcp and one udp mode). FILES
/etc/portsentry/portsentry.conf main configuration file /etc/portsentry/portsentry.ignore IP addresses to ignore /etc/portsentry/portsentry.ignore.static static IP addresses to ignore /etc/default/portsentry startup options /etc/init.d/portsentry script responsible for starting and stopping the daemon /var/lib/portsentry/portsentry.blocked.* blocked hosts(cleared upon reload) /var/lib/portsentry/portsentry.history history file SEE ALSO
portsentry.conf(5), hosts_access(5), hosts_options(5), route(8), ipfwadm(8), ipchains(8), iptables(8), ifconfig(8) /usr/share/doc/portsentry/README.install AUTHOR
portsentry was written by Craig H. Howland <>. This manual page was stitched together by Guido Guenther <>, for the Debian GNU/Linux system (but may be used by others). Some parts are just a cut and paste from the original documentation. PORTSENTRY(8)
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