4 votes

One Static IP - Multiple Web server - Mikrotik RouterOS

As Microtik seems to not have a reverse proxy feature, you will need to implement it separately, in order to redirect requests from a specific domain to a specific server. Here is an explanation from ...
ramius's user avatar
  • 853
3 votes
Accepted

arptables not working with nmap

I'll complete OP's setup: address 192.168.1.38/24 on eth0 and a gateway (not really needed) 192.168.1.1. If the setup uses Wifi rather than actual Ethernet, the first method (bridge) won't be ...
A.B's user avatar
  • 36.7k
2 votes

KDE Connect Not Working [Ubuntu 16.04] : KDE Connect is not discovering phone and vice versa

Open port ranges 1714:1764/udp and 1714:1764/tcp If you use ufw: in /etc/ufw/applications.d/, create file text named kdeconnect and add [kdeconnect] title=KDE Connect description=Device ...
tuxnux's user avatar
  • 21
2 votes
Accepted

choosing firewall: ufw vs nftables vs iptables

There are essentially two separate firewall stacks in the kernel: the older iptables-based stack, and the newer nftables-based stack. However, because some programs are designed to work with one and ...
bk2204's user avatar
  • 4,109
2 votes
Accepted

UFW Couldn't determine iptables version

You could use strace -f -s 1000 -e trace=file ufw status to figure out which files path are used, you could discover something wrong.
Gilles Quénot's user avatar
1 vote
Accepted

Tracing iptables Rules

So, what am I missing, here? The -v option for verbose: -v, --verbose Verbose output. This option makes the list command show the interface name, the rule options (if any), and the TOS masks. The ...
A.B's user avatar
  • 36.7k
1 vote
Accepted

Install apache, php and mysql on Ubuntu 22.04 toolbox

You are in toolbox (a container) which doesn't have its own networking stack. Since toolbox runs in host networking mode, it should inherit whatever firewall rules you set outside toolbox. Have you ...
Cadence's user avatar
  • 126
1 vote
Accepted

nftables - multicast packets not matched

Having reproduced (and completed missing parts for) the setup with a few additional entries such as: nft insert rule filter_4 new_out_4 counter meta pkttype host counter indeed the property meta ...
A.B's user avatar
  • 36.7k
1 vote

iptables rule not working as expected

Traffic goes both ways, especially for TCP: to get traffic from lan0.7 to lan0.17, reply traffic, from lan0.17 to lan0.7, starting with the initial reply: SYN/ACK, has to be allowed, else ...
A.B's user avatar
  • 36.7k
1 vote
Accepted

Iptables: order of redirect and input-filter

The PREROUTING chain in the nat table handles the redirection for you: iptables -t nat -I PREROUTING --protocol tcp --dport 443 --jump REDIRECT --to-port 9443 Then the INPUT chain (implicitly in the ...
Chris Davies's user avatar
1 vote
Accepted

How to flush the nft flowtable hash of active connections?

Offloaded traffic is still associated with a conntrack entry with the property [OFFLOAD] (offloaded entries have a default 30s inactivity timeout and revert to non-offloaded conntrack entries without ...
A.B's user avatar
  • 36.7k
1 vote
Accepted

Load iptables or nftables rules as fast as possible during boot and before the network interfaces be put online

In Debian 12, iptables is by default a wrapper for the new nftables subsystem. The iptables-persistent package depends on package netfilter-persistent, which creates a service named netfilter-...
telcoM's user avatar
  • 97.1k
1 vote
Accepted

RHEL 6.4 basic firewall rule port 6162 does not take effect

Your port 6160 works because it seems to have a Veeam Installer Service running (process name is something like veeamdeploymen* according to your netstat -tulpn output). Because there is no service ...
telcoM's user avatar
  • 97.1k
1 vote

How to block a range of ip adresses with libirt's nwfilter for a specific mac(VM)

According to the documentation, there are no start or end` attributes supports for IPv4 rules. Your options are: srcmacaddr srcmacmask dstmacaddr dstmacmask srcipaddr srcipmask dstipaddr dstipmask ...
larsks's user avatar
  • 34.9k
1 vote
Accepted

nftables doesn't see KDE Connect packets between two machines on the same interface

Warning: this is a generic Linux answer. What won't be covered in this answer is specific integration with NixOS and its own method for configuring network or how to call arbitrary commands from its ...
A.B's user avatar
  • 36.7k
1 vote

Firewalld: How to whitelist just two IP-addresses, not on the same subnet

This is a very good question. firewalld interacts with iptables which in turn interacts with netfilter. Therefore iptables has more flexibility than firewalld. But this does not mean that you must ...
Bruce Malaudzi's user avatar
1 vote

How to protect against port scanners?

The accepted answer provided by @ibrahim is very good but iptables is deprecated and modern systems use nftables instead. So if you guys wonder how to convert his iptables code to nftables then below ...
metablaster's user avatar

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