Difference between revisions of "Fail2Ban"

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(Created page with "<syntaxhighlight lang="console"> # apt install fail2ban </syntaxhighlight> Category:Install")
 
(Add configuration)
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<syntaxhighlight lang="console">
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Debian Stretch (currently in testing) contain a much nicer version of fail2ban than Jessie (current stable). Configuration has been simplified a lot between the two releases and installing the version from stretch will save you migration pain later.<syntaxhighlight lang="console">
# apt install fail2ban
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# apt install fail2ban/stretch
 
</syntaxhighlight>
 
</syntaxhighlight>
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== Configuration ==
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=== Defaults ===
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Create file <code>/etc/fail2ban/jail.local</code><syntaxhighlight lang="ini">
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[DEFAULT]
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# Destination email for action that send you an email
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destemail = fail2ban@mydomain.example
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# Sender email. Warning: not all actions take this into account. Make sure to test if you rely on this
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sender    = fail2ban@mydomain.example
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# Default action. Will block user and send you an email with whois content and log lines.
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action    = %(action_mwl)s
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</syntaxhighlight>
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=== Recidive ===
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<syntaxhighlight lang="ini">
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# Jail for more extended banning of persistent abusers
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# !!! WARNINGS !!!
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# 1. Make sure that your loglevel specified in fail2ban.conf/.local
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#    is not at DEBUG level -- which might then cause fail2ban to fall into
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#    an infinite loop constantly feeding itself with non-informative lines
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# 2. If you increase bantime, you must increase value of dbpurgeage
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#    to maintain entries for failed logins for sufficient amount of time.
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#    The default is defined in fail2ban.conf and you can override it in fail2ban.local
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[recidive]
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enabled  = true
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logpath  = /var/log/fail2ban.log
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banaction = iptables-allports
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bantime  = 86400 ; 1 day. If you
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findtime  = 86400 ; 1 day
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maxretry  = 3
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protocol  = all
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</syntaxhighlight>
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[[Category:Install]]
 
[[Category:Install]]
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[[Category:Fail2Ban]]

Revision as of 15:57, 3 January 2016

Debian Stretch (currently in testing) contain a much nicer version of fail2ban than Jessie (current stable). Configuration has been simplified a lot between the two releases and installing the version from stretch will save you migration pain later.

# apt install fail2ban/stretch

Configuration

Defaults

Create file /etc/fail2ban/jail.local

[DEFAULT]
# Destination email for action that send you an email
destemail = fail2ban@mydomain.example

# Sender email. Warning: not all actions take this into account. Make sure to test if you rely on this
sender    = fail2ban@mydomain.example

# Default action. Will block user and send you an email with whois content and log lines.
action    = %(action_mwl)s

Recidive

# Jail for more extended banning of persistent abusers
# !!! WARNINGS !!! 
# 1. Make sure that your loglevel specified in fail2ban.conf/.local
#    is not at DEBUG level -- which might then cause fail2ban to fall into
#    an infinite loop constantly feeding itself with non-informative lines
# 2. If you increase bantime, you must increase value of dbpurgeage
#    to maintain entries for failed logins for sufficient amount of time.
#    The default is defined in fail2ban.conf and you can override it in fail2ban.local
[recidive]
enabled   = true
logpath   = /var/log/fail2ban.log
banaction = iptables-allports
bantime   = 86400 ; 1 day. If you 
findtime  = 86400 ; 1 day 
maxretry  = 3 
protocol  = all