Questions tagged [firewall]
a technological barrier designed to prevent unauthorized or unwanted communications between computer networks or hosts
1,235
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I'm attempting to execute a Flask test file, but when attempting to access it through the browser, an error stating that the site cannot be reached
I have tried creating an inbound rule in my firewall to allow port <5000> but its still showing site cannot be reached.
i have also tried to Check UFW (Uncomplicated Firewall) with this command
'...
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1
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159
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Can only access some servers on Linode VLAN
I am running a VLAN applied to a number of servers on Linode. The IPs assigned are 10.0.16.n/24 and are accessed via an OpenVPN server also on the same range.
I have connected to the VPN box from my ...
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The download manager loses its access to the Internet after working for a while in ubuntu 23.10.1
I use download manager in Ubuntu but after a while it works fine and the internet access is blocked!
I tested Free Download Manager and Xtreme Download Manager both of them at first work correctly but ...
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Setting up a reverse proxy on home lab
I'm very new to Linux and bash. I'm working on a homelab (machine a) project.
My ultimate goal is to set up Nginx on my server and connect externally (machine c) to Docker apps File Browser, possibly ...
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How to deal: external Jenkins port does not work
I have jenkins service working fine on internal and local levels (I can just open localhost:8080 or 192.168.x.x:8080 in the browser and it gives me Jenkins "sign in" page)
But I have ...
4
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1
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557
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I can't connect to Ubuntu server from local network, but can from outside
This is a weird one that has been driving me crazy for a while. I just can't work it out.
I'm running Ubuntu 22.04 (with all latest patches) on a Dell PowerEdge-r710 server. It's hosting a variety of ...
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UFW block internet connection while using proxychains, How could I configure UFW?
I downloaded Tor, I edited proxychains.conf, uncommented dynamic_chain, proxy DNS - no leak for DNS data, proxy DNS. I added at the end of the proxychains.config file 5 different socks5 server IPs and ...
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Ubuntu Router configuration with UFW
Going down the ubuntu 20.04 server route and using UFW.
Steps so far (from a clean install)
Network Layout attached
networking configured with netplan - YAML file below - question here is do I need ...
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140
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BIND9 on Ubuntu 20 - Cannot configure Zone to work properly
I installed it on Ubunto 20 and configured two zones
Options config file
acl internal {
localhost;
localnets;
192.168.70.0/24;
10.200.157.0/24;
};
options {
...
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129
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Restrict access to Docker container port to ip adresses
There are several docker containers on my server, exposing ports. Now I try to restrict the access to the ports to IP-Adresses being able to insert rules without allowing the policy. I apply IP-Tables ...
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SSH Connection Timed Out Ubuntu 20.04
I've looked through a million threads on this topic but nothing has worked. I'm trying to ssh into my linux through port 22. Connection is refused.
UFW is inactive and firewall-cmd is not downloaded
...
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Ubuntu 22.04 UFW NAT problems
I've done an in-place upgrade from Ubuntu 20.04 to 22.04 and I've found that NAT no longer functions on this firewall box. Before the upgrade, the private network could reach the Internet just fine. I'...
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1
answer
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22.04 - ufw/ip tables could not fetch rule set
I'm trying to get UFW up and running on a Raspberry Pi 4 running Ubuntu server 22.04. But I am at a loss.
# via SSH session:
~$ sudo ufw status
ERROR: problem running iptables: iptables v1.8.7 (...
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Automatically created iptables rules created by Docker seem strange
Here are the rules that I don't understand (those are created automatically by docker on my ubuntu machine):
-A FORWARD -i docker0 ! -o docker0 -j ACCEPT
-A FORWARD -i docker0 -o docker0 -j ACCEPT
So ...
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External HTTPS succeed, internal HTTPS requests timeout on home server
I am running Ubuntu Server 22.04.3. I am using it to serve an API built on Flask, which goes through Gunicorn and NGINX to hit the outside world. The server works as expected for requests served over ...
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How to disable Internet connection for a single process?
I know the PID of a specific process and I want to disable the Internet access for this process and only for this process, so other process can access Internet.
Is there any way to do it?
I ...
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Port Forwarding to another machine Rust gameserver
I need to forward UDP port 28015 of my local machine to another machine with port UDP 28021. Rust Game Server. (Redirect incoming traffic on a specific port to a different IP address with altern port)
...
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UFW allow all IP from ASN
How to allow access to ubuntu with UFW firewall for all addresses belonging to one ICT provider with its ASN number (Is it possible?)?
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cant enable UFW firewall
I am trying to set up a code-server on my ubuntu 22.04.
However I came to the realisation that my firewall wasnt enabled and tried enabling it using the instructions on this other thread : https://...
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3
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What is MASQUERADE in the context of iptables?
In iptables many times I see the target MASQUERADE. What is that? I searched and found lots of things. But I need someone to explain to me what MASQUERADE is in an easy to understand way?
An ...
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6
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UFW firewall still blocking SMB despite adding rules
I have an Ubuntu PC with ufw firewall (GUI version). I have added the preset Samba service, in and out, and even tried adding the ports manually (135-139, 445, UDP and TCP, in and out), but it still ...
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5
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Block China with iptables
I just logged in on a GitLab server and noticed that it had 18.974 failed logins since I last checked the server - almost 5 days. I checked the Ip's and it seems that almost all of them were from ...
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wireguard + ufw = unable to limit access to specific port
So I'm trying to limit access to port 5432 (postgres) by using ufw and unable to do so. The connection is allowed still
sudo ufw deny 5432/tcp
sudo ufw route deny in on wg0 from 10.0.10.2
root@vpn-...
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Connection via SSH works once or twice then never again for that client
I have recently set up a Ubuntu Server minimized. I initially used the server through an SSH with client1 but after one use I kept getting Connection Timed Out when attempting to ssh from client1. I ...
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Cannot access samba from outside LAN
I have samba server running on Ubuntu 22.04. I wish to access it from external machines. If a device is on the same local network I am able to open the smbd:// network address no problem (using the ...
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1
answer
624
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UFW blocking port forwarding
I am running Ubuntu Server as a home network router, which works fine otherwise. I also have another server on the network which hosts all of my content and services. So let's say, for example, I'm ...
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1
answer
548
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ufw not logging on ubuntu 22.04
I have no ufw logs on my minimized Ubuntu 22.04 server.
sudo ufw status verbose output:
$ sudo ufw status verbose
Status: active
Logging: on (low)
On the internet I found I need rsyslogd enabled. On ...
2
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1
answer
344
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UFW - Default Deny Incoming does not block telnet
I have an Ubuntu 22.04 LTS Server setup on a VM. I have ufw enabled with default deny incoming policy
The result of sudo ufw status verbose is:
Status: active
Logging: on (low)
Default: deny (incoming)...
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1
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51
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Is this a good firewall to keep brute force atackers out?
I am wondering, is the script below a good firewall script to keep brute force attackers out off my desktop?
iptables -F
iptables -A INPUT -i lo -p all -j ACCEPT
iptables -A OUTPUT -o lo -p all -j ...
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1
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IP addresses of ubuntu servers which apt-get connects
My server uses Ubuntu 22.04 LTS. I have a very restricted firewall (UFW), that is, I have run these commands:
sudo ufw default deny outgoing
sudo ufw default deny incoming
But, I would like my system ...
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634
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curl to localhost fails in 20.04
I have host machine 20.04 and guest VM box 22.04
I am trying to run the curl command and on both machine getting the same error.
Host running this:
sudo ufw status
Status: active
To ...
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1
answer
47
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Network card issues after reinstall of 20.04
PC with PCI Lan card and motherboard Lan had previously worked fine on 18.04 and 20.04, was upgraded to 22.04 but found application compatibility issues so reinstalled 20.04. Now the integral Lan is ...
23
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9
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Alternative to Little-Snitch app-firewall?
I'm trying out Ubuntu. Been a Mac user. I like ubuntu a lot but I'm uncomfortable not having an app-firewall that reports what connections are being made to the internet. I find it unnerving to not ...
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4
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Port seems to be open, but connection refused
I am trying to open port 3000 on Ubuntu 12.04, cause I have a web server listening there. I'm a bit out of my confort zone here, and spent many hours trying to solve the problem without success.
Port ...
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Diference between IPTABLES RAW PREROUTING and MANGLE PREROUTING
I'm looking for configs to prevent DDoS attacks and UPnP Flood, since I've started to create rules, every advice was to add rules to filter table, but it takes too much CPU process, so started to ...
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Why ports added to firewall are still closed?
I have added ports 25 and 80 to the firewall and enabled the firewall but even after reboot when I check the ports, they are still closed?
What else do I have to do?
Warmest regards
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How do I know if my firewall is on?
I installed Firestarter, and configured my firewall.
But I'm in doubt : On boot, I sometimes see a [FAIL] marker, and to the left, I guess it was something like "start firewall". I can't be sure ...
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1
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Can't connect to remote MySQL (v. 8.0.33 | ubuntu 22.04.2)
On the server with the operating system ubuntu 22.04.2 installed MySQL version 8.0.33 with the following configuration:
/etc/mysql/mysql.conf.d/mysqld.cnf
#
# The MySQL database server configuration ...
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Ubuntu iptables
How to accept traffic coming from server1 to server 2 and route to internet from server 2
Server 1 doesn't have internet connection it should get routed from server 2
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Ports are set to allow in ufw but shows blocked
I am very new to using ubuntu, I was trying to configure my plesk email but realized I am not able to receive or send emails. I have configured the correct ports with ufw allow, but they show blocked ...
105
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11
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77k
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Uncomplicated Firewall (UFW) is not blocking anything when using Docker
This is my first time setting up an Ubuntu Server (14.04 LTS) and I am having trouble configuring the firewall (UFW).
I only need ssh and http, so I am doing this:
sudo ufw disable
sudo ufw reset
...
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1
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How do I use UFW to block a device in Ubuntu hotspot?
I have a laptop running Ubuntu 20.04, which connected to the internet via ethernet.
I have setup a WiFi hotspot on this machine, so that I can share its internet connection.
Say, I have third device (...
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allow certbot validation and github action connection to digitalocean network firewall
I have this digitalocean droplet that I served as staging instance and has network firewall on it. As it is a staging instance I made it work like a private access only by adding our outline vpn ip on ...
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Unable to remote access the web server running on Ubuntu machine
I'm unable to remote access nginx server or express server or any server running on Ubuntu in the same network
I tried every solution found on Google, chat gpt but no benefit
I'm able to ssh on Ubuntu ...
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1
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456
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SSH configured ports not working
Just installed Kubunut 22.10. I configured my /etc/ssh/sshd_config with a custom port.
# Snip
Port 5555
AllowUsers bob
# Snip
Then restart the daemon to refresh the configuration:
sudo ufw allow 5555
...
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0
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Is there anyway to block/whitelist certain ASN number on Ubuntu?
I knew how to configure ufw or (iptables), but how do I whitelist certain ASN number on Ubuntu?
lsb_release -a
Distributor ID: Ubuntu
Description: Ubuntu 20.04.6 LTS
Release: 20.04
Codename: ...
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Ubuntu - Tool for UDP rate-limit
I have a SIP gateway machine that I would like to apply some kind of rate limit on the host machine.
Something like - If an X number of connections happens under Y seconds -> Block source-IP and ...
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Uable to connect Ubuntu server by remoting
Hello I'm newbie of Ubuntu system. I have some problem that I've figured out for a while but I could not solve it yet. I could not remote to Ubuntu 22.04 server from my laptop (Putty said connection ...
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Port forwarding not working
I have a machine on my home network I am trying to port forward (for rust if that helps) and I need to get these done
TCP: 27015, 27036, 28016, 28083
UDP: 27015, 27031-27036, 28015
I have allowed all ...
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649
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Install outline VPN on a NAT VPS
I'm trying to install outline on my NAT server, but I keep getting this error:
Your Outline Server was installed correctly, but we are not able to connect to it. Most likely this is because your ...