The Wiert Corner – irregular stream of stuff

Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

  • My badges

  • Twitter Updates

  • My Flickr Stream

  • Pages

  • All categories

  • Enter your email address to subscribe to this blog and receive notifications of new posts by email.

    Join 1,604 other followers

Archive for the ‘iptables’ Category

iptables debugging « \1

Posted by jpluimers on 2017/11/28

Using the TRACE target: [WayBackiptables debugging « \1 via [WayBack] iptables Debugging using the TRACE chain – Kristian Köhntopp – Google+

Docs:

TRACE
This target marks packes so that the kernel will log every rule which match the packets as those traverse the tables, chains,
rules. (The ipt_LOG or ip6t_LOG module is required for the logging.) The packets are logged with the string prefix: “TRACE:
tablename:chainname:type:rulenum ” where type can be “rule” for plain rule, “return” for implicit rule at the end of a user
defined chain and “policy” for the policy of the built in chains.
It can only be used in the raw table.

Way more details in the linked article.

–jeroen

Posted in *nix, *nix-tools, Firewall, Infrastructure, iptables, Power User | Leave a Comment »

linux port forwarding to external ip – Google Search

Posted by jpluimers on 2017/01/20

For my Link Archive via linux port forwarding to external ip – Google Search:

Need to look at this more closely, but it looks like you need PREROUTING, FORWARD and POSTROUTING and two NATs (DNAT and SNAT), as this graph from Port Forwarding Using iptables – SysTutorials shows:

PACKET IN
    |
PREROUTING--[routing]-->--FORWARD-->--POSTROUTING-->--OUT
 - nat (dst)   |           - filter      - nat (src)
               |                            |
               |                            |
              INPUT                       OUTPUT
              - filter                    - nat (dst)
               |                          - filter
               |                            |
               `----->-----[app]----->------'

–jeroen

Posted in *nix, *nix-tools, Internet, Internet protocol suite, iptables, Linux, openSuSE, Power User, Routers, SuSE Linux, TCP | Leave a Comment »

Fighting with IPv6 – There and back again

Posted by jpluimers on 2016/01/09

Interesting:

During the last weeks I finally got my hands dirty with IPv6. A comment on my blog and an email informed me that my server (hosting this blog) is not reachable via IPv6, albeit it has an IPv6 address. That said, I tried to get that running and fell into several holes, due to firewalls, […]

Source: Fighting with IPv6 – There and back again

Posted in *nix, *nix-tools, Apache2, iptables, Linux, Power User | Leave a Comment »

 
%d bloggers like this: