Questions tagged [firewall]
A firewall is a program that controls the incoming and outgoing network traffic on a system. Use this tag for all questions related to firewall configuration and operation.
1,069 questions
2 votes
2 answers
155 views
I'm confused. Is my UFW firewall working or not?
Linux Endeavouros. I don't understand how to tell if my firewall is on or not. Using systemctl status ufw gives: ufw.service - CLI Netfilter Manager Loaded: loaded (/usr/lib/systemd/system/ufw....
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0 votes
0 answers
100 views
How to idiomatically secure a Fedora Workstation system against all incoming connections?
Dear ServerFault community! I run Fedora Workstation (currently version 42) on my laptop, and would like to configure my firewall to just reject or drop all incoming connections to keep my system ...
- 13
0 votes
0 answers
46 views
Problem using "dynamic" maps with nftables
I want to create an nftables filter rule that drops traffic where the source and destination address are equal. Nftables only allows to compare addresses against constants or sets/maps. So I tried to ...
- 1
0 votes
1 answer
53 views
iptables changes not having any effect [closed]
I was attempting to interrupt a TCP connection on my system, and was altering iptables rules using the iptables command. Nothing I did seemed to have any effect, though. Inserting and deleting rules ...
- 175
1 vote
1 answer
123 views
How to enable the listing of Chromecast devices in the full network (mDNS): Chromecast devices are not showing in VLC or Chromium
Chromecast is working well in my home (trough multiple switches connecting different rooms) but I am unable to cast from my openSUSE Linux device. The Chromecast devices are not showing up neither in ...
- 111
1 vote
2 answers
137 views
Does Linux have a generic way to dynamically open ports? (Desktop)
By generic, I mean, mostly standard, i.e. not dependent on ufw or firewalld. What I am asking is if there is something akin to what you have on Windows, where if some game wishes to "Open to Lan&...
- 273
0 votes
1 answer
62 views
Iptables does not apply drop policy for other ports
I'm running a server where iptables is configured with a default DROP policy and I’ve only explicitly allowed certain ports (e.g., HTTP, HTTPS, SSH on port 22, etc.). Despite never adding a rule for ...
2 votes
1 answer
295 views
libvirt kvm virtual routed network: cannot ping gateway itself or beyond
I'm having trouble with libvirt kvm's routed networks where a VM inside a routed virtual network can ping every VM in my home subnet except the default gateway... or any gateway for that matter. I ...
- 21
0 votes
1 answer
52 views
Unable to change firewall active zone
I am trying to update my firewall but now i want to revert it back to public so basically the firewall is running and it was public (active) target: default icmp-block-inversion: no interfaces: ...
- 1
0 votes
0 answers
129 views
NFTables tables, hooks and rules ordering
I'm new to nftables but have used iptables for quite a while now. While playing with nftables, I was thinking: "Hey, this is cool, I could have like a management table, where all the mngt stuff ...
0 votes
1 answer
71 views
IPFW documentation
I am setting up router inside freebsd jail with ipfw, I might be blind, but I could not find comprehensive documentation on IPFW, which would make subject clear. I read both "firewall" and &...
0 votes
0 answers
56 views
HTTP/HTTPS Packets Getting Dropped [nftables]
I am using the ebtables broute table to selectively "deny up" HTTP/HTTPS packets - I want to process them at the IP (L3) layer with nftables. I am having this problem where the packets are ...
0 votes
1 answer
197 views
Firewall in Bridged LXC Containers
I am new to networking, and I am trying to implement a firewall inside an LXC container (Alpine Linux) that is bridged with another LXC container (Alpine Linux) through a br0 interface. Right now, my ...
- 101
1 vote
0 answers
56 views
NFtables unique handle
is nftables use unique handle ? I mean it's possible to have a handle id used on both table and rule or chain ? if handle is unique . What is unique strategy ? For example : Unique on whole nftables ...
- 318
1 vote
1 answer
113 views
Ask for validation of nftables rule for throttling SCTP/DIAMETER AIRs
I'm trying to build an nftables rule which can throttle SCTP traffic which contains DIAMETER. I would further like to only drop Authentication Information Requests (AIR). So in general everything ...
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