why is iptables still filtering after i disable the firewall?

[Robert P. J. Day]

On Wed, 15 Sep 2010, Christopher Chan wrote:

> Robert P. J. Day wrote:
> >   i suspect this is based on my unfamiliarity with the way ubuntu
> > pre-10.10 deals with firewalls but i'm trying to simply ping from
> > my ubuntu system to a centos 5.5 box on the same in-house wireless
> > network and i'm getting icmp responses, "Destination Host
> > Unreachable."  yet i can ping the other way (centos -> ubuntu).
>
> I would completely uninstall 'uncomplicated firewall' and restart
> the network. Ubuntu's complicated approach to trying to make it
> simple for users to setup firewall rules is just broken.

  ok, i'm still slightly confused but for a different reason.  recall
that i couldn't ssh or even ping from the ubuntu box to the centos
box, ping worked fine coming the other way.

  finally, i ssh'ed in from centos to ubuntu, was asked that first
time to authenticate, RSA key fingerprint, added to known hosts, etc,
etc, you all know the drill.  and, suddenly, i can ping and ssh from
ubuntu to centos.

  from memory, i recall that there's a setting somewhere under
/etc/ssh that restricts communication to only those hosts that have
been authenticated (what is it?).  but does that setting even apply to
non-ssh functionality like ping?  can someone explain what just
happened here?  thanks.

rday

-- 

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Robert P. J. Day                               Waterloo, Ontario, CANADA

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