On 01/02/2013 06:54 PM, Alan Evans wrote:
This is really related to iptables, not I presume Fedora-specific. But
I'm really hoping that somebody here will be able to school me on
iptables, so I don't have to find and subscribe to some other list
just to ask one question.
For what it is worth opinion.
When I had to maintain a Linux firewall, I used Shorewall for all these
rule writing. Shorewall makes sense of the iptables mess.
Now I run a commercial branch office class firewall for my network.
Sometimes I dream of going back and rolling my own, not to put up with
the vendor limitations...
I'm faced with the problem of needing to punch a hole in a firewall on
our portal server so that, in our case, ssh to port 20022 on external
interface of that server actually just connects to port 22 on another
machine located in the network on the internal interface. I hope I'm
being clear.
I've tried many iterations of iptables rules to accomplish this. The
closest I've come is:
iptables -A PREROUTING -t nat -p tcp -s 0/0 --dport 20022 -j DNAT --to
192.168.0.35:22 <http://192.168.0.35:22>
And indeed connecting to port 20022 on portal just goes straight to
port 22 on the other (192.168.0.35) machine. The problem is, as soon
as I apply this rule, DNS queries (portal is also a DNS server) to the
external interface stop working.
I've googled endlessly and found about a thousand variations by people
that are each supposed to solve a subtly different variation on what
I'm trying to do. Nothing I've tried does what I want without bad side
effects like I describe above.
-Alan
--
users mailing list
users@lists.fedoraproject.org
To unsubscribe or change subscription options:
https://admin.fedoraproject.org/mailman/listinfo/users
Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
Have a question? Ask away: http://ask.fedoraproject.org
