/etc/hosts.allow versus iptables/firewall?

What's the relation between the /etc/hosts.allow and /etc/hosts.deny files, on the one hand, and a host firewall on the other? If I'm going to configure iptables on a machine, is there any point to having any non-trivial rules in /etc/hosts.allow and /etc/hosts.deny too? Or should I just set them to let everything connect and do all my configuration through iptables?
(Well, really, I'm going to use some iptables-for-dummies tool like ufw or firehol.)

I cannot agree that hosts.{allow,deny} are 'a lot more basic' They're different from iptables, they work on different level and offer different capabilities, but it would be much harder with iptables to grant/deny access according to:
- ident lookup
- NIS netgroup
- domain name
- consistent ip->name and name->ip mapping
and so on; man 5 hosts_access and man hosts_options contain some examples. On the actions side, in addition to granting or denying access, arbitrary command can be run in parallel or instead of called service, with some useful informations about connection available as %variables.
Tcp_wrappers do not have to be called by protected service itself; they can be used with everything that uses TCP and can be run via (x)inetd, with a little help from tcpd(8).
I prefer iptables myself (no use in letting unwanted traffic pass any further than strictly necessary), but tcp_wrappers make a really nice and useful complementary solution.

Similar Messages

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  • Sshd ignores /etc/hosts.allow and /etc/hosts.deny

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    elasticdog wrote:So should our package not have the ListenAddress 0.0.0.0 line uncommented by default?  My guess would be that since it listens on all local addresses by default, we're just overwriting that when specifying 0.0.0.0, which isn't valid.  That was users don't have to specify their local IP address.  Unless I'm wrong, shouldn't this be a bug/feature request for the packager?
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  • Syntax of ip ranges in /etc/hosts.allow

    How does one define a range of IP addresses in the /etc/hosts.allow?  Pasted from the ssh wiki article
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    You can't do this on a single line AFAIK since .2 to .10 doesn't fit in any valid CIDR mask. You will need to add a line for each host individually:
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    Last edited by fukawi2 (2009-06-06 22:45:26)

  • Tcp wrappers /etc/hosts.allow format

    since most of the services that were originally run from
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    elasticdog wrote:So should our package not have the ListenAddress 0.0.0.0 line uncommented by default?  My guess would be that since it listens on all local addresses by default, we're just overwriting that when specifying 0.0.0.0, which isn't valid.  That was users don't have to specify their local IP address.  Unless I'm wrong, shouldn't this be a bug/feature request for the packager?
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  • Having issues-/etc/hosts.deny /etc/hosts.allow!

    OK-I just did an install of Arch '09 x86_64 core on my HP Pavillion a810n AMD Athlon64 3300+. I got to the part about configuring and the directions just aren't very clear...What EXACTLY do I input to both deny/allow to be able to get on the net to install gnome/X, etc??
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    Thanks.

    From the Beginners Guide:
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    What is the exact error(s) you are receiving?
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  • Pure-ftpd setup (hosts.allow & hosts.deny)

    hello,
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    If your version of pure-ftpd was build without tcpwrappers, but might explain it.

  • Hosts.allow option spawn parameter not work

    Hi,
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    I tried several configurations with different sshd entries and results are below
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    Last edited by xnovako2 (2010-02-20 16:53:23)

    the Access files are read in order of /etc/hosts.allow, and /etc/hosts.deny
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    http://linux.die.net/man/5/hosts.allow
    use the above link for a complete help on this.

  • Is SID allowed to show up in /etc/hosts file?

    Experts:
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    Hi,
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  • Lenovo W530/W540 Getting Destination host Unreachable from our Firewall

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  • Adding the /etc/host.deny file like linux in solaris 10.

    Dears,
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    IPfilter can deny a specific IP address access to the host - enable IPFilter with svcadm and edit the /etc/ipf/ipf.conf file to add the IP to block. An example could be:
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  • Oracle 11gR2 RAC VM and SCAN and DNS and /etc/hosts (two) setup questions

    Hi,
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    AIM wrote:
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  • How could a java process bypass etc\hosts file while doing dns lookup ?

    Hi,
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  • Proper /etc/hosts for my situation

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    Thanks.

    Hi,
    In the etc/hosts you have add ur ip address with hostname, something like this it should be.
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    because, i think so,so here is what my /etc/hosts file looks like
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    127.0.0.1 localhost.localdomain localhostFor the below TNS lost contact error, recently I faced a similar kind of error:
    and the error i am right now getting is this
    [oracle@unknown485b39d0b515 ~]$ sqlplus "/as sysdba"
    SQL*Plus: Release 11.2.0.1.0 Production on Wed Aug 8 12:03:27 2012
    Copyright (c) 1982, 2009, Oracle. All rights reserved.
    ERROR:
    ORA-12547: TNS:lost contact
    Check your ORACLE_HOME/bin folders rights.
    $ ls -ltr oracle
    -rwxr-xr-x 1 oracle dba 25485683 Jul 2 12:02 oracle
    $ chmod 6751 oracle
    $ ls -ltr oracle
    -rwsr-s--x 1 oracle dba 25485683 Jul 2 12:02 oracle
    And check whether your user has dba group.
    This may help you..
    Thanks,
    nonuday

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