All Questions
58
questions
2
votes
1
answer
83
views
Tracing iptables Rules
I'm just beginning to dig into iptables for the first time today, so apologies for any naivete.
For reference, I'm using
Ubuntu 22.04.4 LTS (Jammy Jellyfish)
iptables v1.8.7 (nf_tables)
ufw 0.36.1
...
0
votes
0
answers
28
views
Many UFW BLOCKs pr minute from numerous ports and numerous IP addresses
My syslog is flooded with numerous attacks of some sort coming from multiple sources.
I looked at all the other references in the search feature but none addressed tcp and from numerous sources
Feb 16 ...
- 207
2
votes
1
answer
4k
views
Ubuntu 22.04 iptables command not working
Totally new to netfilter thing, currently am running an application which uses three interfaces eth0/eth1/eth2, my application will run on two servers and they both can communicate between them via ...
- 169
0
votes
0
answers
95
views
ufw rule supposed to block traffic but iptables allows it
As a test I wanted to temporarily block access to my website. So, I deleted http/https rules using ufw delete command. ufw is set to default deny incoming. The only remaining rule is the one allowing ...
- 179
0
votes
1
answer
194
views
How to define port forwarding
I run a server with a web server running as a rootless podman container. This exposes ports 10080 and 10443 because, as a rootless container, it is not allowed to expose ports 80 and 443.
So that my ...
- 1
2
votes
1
answer
3k
views
UFW Couldn't determine iptables version
I am building a custom embedded Linux platform based on the NXP i.MX8 with Yocto. I want to use UFW to setup the firewall. When I boot the system and try to use UFW it returns an error
Couldn't ...
- 29
0
votes
1
answer
95
views
Firewall : firewalld with docker open port for local service
I'm trying to open port for ssh on non-standard port like 12452, i used these commands and non of them worked
iptables -I INPUT -p tcp --dport 12452 -j ACCEPT
iptables -I OUTPUT -p tcp --dport 12452 -...
- 123
0
votes
1
answer
316
views
Enable NAT with TCPMSS using UFW
I could enable NAT using UFW with following configuration.
*nat
:POSTROUTING ACCEPT [0:0]
-A POSTROUTING -s 192.168.141.0/24 -o ens192 -j MASQUERADE
COMMIT
If I want to enable TCPMSS, I have to run ...
- 31
5
votes
0
answers
2k
views
Ubuntu 22.04 firewalld initiation problem: no python-nftables
I tried to use firewalld instead of ufw, but it keeps showing the following errors even after manually downloading python-nftables through sudo apt install
iptables is not being used.
$ systemctl ...
- 51
0
votes
1
answer
3k
views
Why can't apt find my desired version of iptables?
I am trying to install version 1.6.2 of iptables in ubuntu 22.04. (Please note: This is about iptables 1.6.2. I have no trouble installing iptables 1.8.7, but I need 1.6.2.)
root@924516f76c4c:/var/...
- 141
1
vote
0
answers
159
views
Prevent network namespaces / lxd-bridges from talking to each other, but keep internet access?
Following goal:
I have lxd containers
each set of containers should have their dedicated isolated network
each should still be able to connect to the internet (e.g. apt update or curl), but not leak ...
- 11
0
votes
1
answer
541
views
Redirecting DNS querries from NAT'd devices and UFW
I'm having a tough time figuring this one out.
I have the following network:
(Internet)--(firewall) -- (PC1 (Ubuntu 20.04)) -- (PC2 (Fedora, 192.168.0.2))
PC1 has two NICs, (enp4s0) faces the firewall,...
- 41
1
vote
1
answer
3k
views
Why am I getting connection refused with IP address even though it works with localhost and firewall is open?
When I run sudo ufw status on a Ubuntu box, I get the following output
sudo ufw status
Status: active
To Action From
-- ------ ----
22/tcp ...
- 121
0
votes
1
answer
3k
views
UFW Masquerade and outside traffic only on specific interfaces
I have a Ubuntu system (192.168.A.B) that is running as a Wireguard "server" with 2 tunnels with the following networks and UFW rules:
Network 10.255.200.0/24
ufw allow XXX/udp && ...
- 103
0
votes
1
answer
505
views
Setting up Port forwarding on Ubuntu 21.10 with OpenVPN (homerouter port forwarding not working)
I'm trying to setup port forwarding on my local workstation, since the home router is not capable of doing the port forwarding I went on with privateVPN. The privateVPN is configured on OpenVPN with ...
- 1