Questions tagged [ufw]
Uncomplicated Firewall (ufw)
747
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Firewall rules are saying specific ports are opened. But actually closed
I have purchased an Ubuntu 22.04 vps. I tried to open port 2281, 2282 and 2283. Firewall rules saying ports are opened. But actually they are closed. I also tried using ufw. But nothing works.
Before ...
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0
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1
answer
61
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How come IPv6 works with UFW default deny outgoing?
So I have 2 questions.
I have an Ubuntu 22.04 VM with netplan configured in the following way:
network:
ethernets:
eth0:
addresses:
- 10.100.100.100/24
dhcp4: false
dhcp6:...
- 449
0
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0
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51
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Kubuntu blocks Internet for virtual machines
The firewall (ufw) of Kubuntu 24.04 blocks the connection of virtual machines to the Internet - when I turn off the firewall there is a connection, so sure, but there are no rules to block the output. ...
- 71
-1
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3
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102
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Concern about security on server
I'm new to Linux/Ubuntu and I'm setting up a Minecraft server to play with friends online. However, I want to ensure my computer isn't exposed to potential security risks. Currently, I've followed ...
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55
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FTP Server responds on localhost, but not pc on same subnet
I am now running Ubuntu 22.04 after recently upgrading from Ubuntu 18.04. I am using the latest vsftpd. I have verified that I can ftp to the localhost and see the contents of the directory once I'm ...
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0
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250
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Ubuntu Server - Restricting ssh access to one IP address
I have a VPS in a datacentre in France. I upload files from my base in Ireland using mobile phone Internet.
My IP seems to be the same from my end. I don't use a proxy but don't know if my mobile ...
- 508
0
votes
1
answer
81
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Disable Internet access but allow chrome extension
I'm trying to deny access to the Internet and that part works with ufw default deny outgoing (the PC is going to be used for exams so no googling allowed;-))
But
I need access to a chrome extension ...
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39
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Ufw output doesn't seem right
Is there any possible way that this command:
sudo ufw status numbered
would output:
enabled
because I can't think of any reason it would, but it did.
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3
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1
answer
309
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What are some precautions to take when doing port forwarding on desktop to establish ssh connection with laptop?
I have a home desktop in another city and a laptop I bring to campus both running ubuntu 22.04.4. I would like to establish a ssh connection from the laptop to the desktop to retrieve and write files.
...
- 71
1
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0
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79
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UFW not logging [UFW BLOCK] events when default is to allow incoming connections
I'm trying to get a message logged to /var/log/ufw.log when blocking packets. It's all working very well, until I change the default behaviour for incoming connections.
I use ufw default allow ...
- 11
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1
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104
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Firewall ufw to deny port visibility
How can I block ports from being visible/accessible from the outside using ufw?
If I nmap my server I can see all my running Docker containers (all ports from 8080 to 8086), which I do not want, ...
- 2,523
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32
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UFW to restrict access on second NIC
I am running a cloud based Ubuntu 22.04 server with a public and with another non routable IP address (DigitalOcean)
I am trying to limit access to the second IP address for a Tinc VPN which uses port ...
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0
answers
89
views
UFW Blocks certain entry repeatedly
I was checking the UFW logs and I see a lot of entries like this
[UFW BLOCK] IN=wlo1 OUT= MAC=01:00:xx:00:00:xx:xx:35:38:xx:xx:xx:08:00 SRC=0.0.0.0 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 ...
- 4,189
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48
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firewall is enable but gufw wont lauch
The firewall is enabled. But I can't launch gufw interface.
sudo ufw status
Status: active
- 1
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1
answer
70
views
Website 504 error when enabling UFW after upgrading from 20.04 to 22.04
After upgrading the server from Ubuntu 20.04 to Ubuntu 22.04, enabling UFW made a website 504 error.
When enabling UFW the error is:
ERROR: problem running ufw-init
iptables-restore: line 4 failed
- 11
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0
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181
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Nginx configuration failure: iptables table does not exist
I tried to configure nginx on my Ubuntu system. During this process, I executed the command sudo ufw allow 'Nginx HTTP and I got an error:
WARN: initcaps
[Errno 2] iptables v1.8.7 (legacy): can't ...
1
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1
answer
135
views
Port not open (ufw disabled)
On the server, running Ubuntu 22.04
sudo netstat -tnlp | grep :4000
tcp 0 0 0.0.0.0:4000 0.0.0.0:* LISTEN 10690/nxd
tcp6 0 0 :::4000 ...
- 113
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1
answer
4k
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Use UFW (firewall) to deny incoming ping (ICMP) requests?
The ufw (uncomplicated firewall) command line app does not have any option for disabling incoming ICMP Internet protocol requests. ICMP is used mainly by ping to discover IP addresses of servers on ...
- 522
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0
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52
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ufw and iptables rules
I have Ubuntu 22.04 running with ufw enabled. For some testing reason I disabled ufw but found that after reboot the rules are active again.
Since ufw is not enabled the old rules are applied to ...
- 3,288
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1
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103
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ufw won't put custom rule in the correct place at reboot
My general issue is that I lose contact with my Ubuntu 23.10 on ssh once I close my ports using knockd. I would like for it to maintain existing connections.
I have a custom rule
> iptables -I ...
- 160
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0
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106
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Why I'm getting these random [UFW BLOCK] requests in my syslogs?
I just noticed large numbers of these random requests getting blocked by UFW
9:34 AM [UFW BLOCK] IN=eno1 OUT= MAC=[MY_SERVER_MAC_ADDRESS] SRC=193.254.3.18 DST=[MY_SERVER_LOCAL_IP] LEN=60 TOS=0x00 PREC=...
- 101
-2
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1
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175
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I want to to disallow everything except ssh, e-mail, and http [closed]
If I use:
sudo ufw default deny incoming
sudo ufw default allow outgoing
sudo ufw allow ssh
sudo ufw allow http
...etc
sudo ufw enable
To block the world from entering my website execpt certain ...
- 15
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0
answers
73
views
Open specific ports of local servers through port forwarding, while block internet access
I have some local servers (192.168.0.100 (x1) ~ 192.168.0.110 (x10), respectively, no public IP),
and they are connected to the internet via a gateway server (192.168.0.1, has public IP).
Internet---&...
- 1
0
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1
answer
298
views
Using Ubuntu 22.04 as DNS Server with bind9
I want to use a simple ubuntu 22.04 server as a DNS Server for my pc.
I created a new server, with a static ip address, that i will type in to my dns in windows.
My problem is, when i try
nslookup ...
- 1
0
votes
1
answer
438
views
vsftpd fails LIST command even when firewall is off and on localhost
I installed vsftpd and am using ufw as my firewall. I can connect to the ftp server, login, and change directories, but any attempt at using a LIST command times out from both external and localhost. ...
- 1
0
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0
answers
117
views
Getting Bunch Of kernel: [UFW BLOCK] IN=wlp1s0 OUT In Journctl
My Ubuntu server goes out of reach after sometime, mean I cant access it through samba and not even SSH works and Apache also shows exit code
When I checked my journalctl I had found bunch of kernel: [...
- 21
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0
answers
207
views
ufw rule to allow address on the same subnet?
I have a server running Linux hosting a website. It uses ufw as a firewall. I have ports 80 and 443 open to external traffic. This all works.
Now what I want to do is allow any traffic from my laptop ...
- 109
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180
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Still getting [UFW BLOCK], which rules apply?
I still get a message UFW BLOCKED:
Dec 22 05:12:41 ge-domoticz kernel: [5324365.003868] [UFW BLOCK] IN=eth0 OUT= MAC=b8:27:eb:a1:7b:8b:38:1f:8d:e9:e4:9f:08:00:45:00:00:28:92:8c:00:00:ff:06:2f:d4 SRC=...
0
votes
1
answer
493
views
ufw blocks DNS response
i've got an ubuntu server (Ubuntu 22.04 LTS) running with svn, duplicati, rdp-forwarding and ssh-access.
My problem is that i cant resolve hostnames within our network an beyond.
sudo apt update is ...
- 1
1
vote
0
answers
109
views
Strange UFW Block Logs
i noticed repeats of the following logs in my server:
Dec 3 21:55:27 alice-server kernel: [287677.084885] [UFW BLOCK] IN=ens18 OUT= MAC=01:00:5e:00:00:01:90:9a:4a:dc:31:62:08:00 SRC=192.168.0.1 DST=...
- 11
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1
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330
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KDE Connecting to Android on Ubuntu 22.04 fire wall settings
When the firewall is disabled, all works just fine. What ports must I permanently set to accept this connection and not compromise the security.
0
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0
answers
386
views
Ubuntu 22.04 iptables command not working
I posted this same question in another SE forum, later felt this forum is more appropriate considering the Linux Distro I am dealing with.
Totally new to netfilter thing, currently am running an ...
- 101
2
votes
1
answer
672
views
Strange dmesg UFW messages... lots of them
I've done some digging but haven't been able to find something that explains below message I found in dmesg? It's obvious the UFW firewall is blocking something, but I am not having any success in ...
- 121
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0
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32
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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
'...
- 1
0
votes
0
answers
523
views
Ubuntu port is open but unable to telnet locally/remotely
I have tried to go through lots of documents/blogs but couldn't resolve my issue.
I have a local Ubuntu 22.04 installed inside vmware workstation with the IP address 192.168.100.108. The server is ...
- 1
0
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0
answers
314
views
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 ...
- 1
0
votes
1
answer
954
views
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 ...
- 1
0
votes
0
answers
20
views
ufw doesn't block ports I expect it to block [duplicate]
I've installed ufw on my VPS and ran the following commands:
# ufw default allow outgoing
# ufw default deny incoming
# ufw allow ssh
# ufw allow 443/tcp comment 'accept HTTPS connections'
# ufw ...
- 226
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148
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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 ...
- 1
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0
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81
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Ubuntu Starts to a black screen with UFW error
I have Ubuntu 20.04(I believe) installed on an old HP Compaq 8200 that I use for projects and whatnot and I've had an issue of it not booting properly. When I turn it on, it does the HP boot, an error ...
0
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1
answer
793
views
Unable to use ufw on ubuntu 20?
I am unable to use ufw on ubuntu 20.
It is already installed(apt install shows already the latest version)
When i type ufw command the output is:
File "/usr/sbin/ufw", line 25, in
import ...
- 145
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0
answers
566
views
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://...
- 1
1
vote
0
answers
654
views
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-...
- 141
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votes
1
answer
492
views
Ubuntu 22.04 on Dell XPS 17 Hangs on Shutdown
When I try to shut down my computer, it hangs on the Ubuntu/Dell splash page. I've used F1 to view the logs, and the last lines are usually the following:
systemd-shutdown[1]: Syncing filesystems and ...
- 3
1
vote
1
answer
894
views
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 ...
1
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0
answers
94
views
How to stop all traffic on metered network
I want to put a Raspberry Pi computer running Ubuntu Server 22.04 with a cellular modem in a weather station on a mountain, and my data plan is metered. I only want to be charged for data relevant to ...
- 635
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0
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1k
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How to allow SSH only from WireGuard and one IP
This is production server and I need to add rules very carefully, I don't sure what is correct rule.
Currently my UFW rules allow SSH connection from any IP and from WireGuard, also my own IP (YYY.YYY....
- 13
-1
votes
1
answer
369
views
Disable outgoing connection via firewall
For a headless setup, I would like to set up ufw so that
ssh into the machine is possible
no outgoing connections are allowed (not ssh, nor anything else; edit: particularly to the local network)
...
- 523
0
votes
0
answers
56
views
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 ...
0
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0
answers
237
views
How to safely open ports for Cyber Protection Agent
I have installed the Backup Agent for Linux Servers "Cyber Protection Agent" on vps.
I have followed this link https://www.ionos.com/help/server-cloud-infrastructure/cloud-backup/installing-...
- 225