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Questions tagged [ufw]

ufw is the default firewall application for Ubuntu Linux.

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17 views

Why does ufw always block the SCTP protocol, regardless of what rules I have?

ufw seems to always block the SCTP protocol whatever rules I have set up: For example, running enabled even with no rules: ufw reset ufw default allow incoming ufw enable I still see SCTP ...
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0answers
14 views

If I only have browser-based firewalls, like uMatrix, should I still be setting up other firewalls, like ufw?

I have a bunch of browser-based protection, set up -- uMatrix, uBlock Origin, HTTPS Everywhere, etc. But, should I be setting up other firewalls (like ufw) to only allow traffic on certain ports of my ...
0
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1answer
18 views

How to make UFW work with firewalld on CentOS 7?

I've installed UFW on a fresh CentOS 7 installation, but it doesn't open the ports. I'm configuring UFW as I would on a Debian system: sudo ufw default deny incoming sudo ufw default allow outgoing ...
1
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1answer
48 views

Exposing service listening to localhost, to public using UFW/iptables

I have a service that listens to 127.0.0.1:15750 and would like to make that service listen to 0.0.0.0:15750 using just UFW (or iptables if not possible with UFW). Basically listen same port (or not ...
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0answers
24 views

Server not appearing to public with VPN

I have a VPS with OpenVPN and I have connected my server to the VPN, on the server I can web browse and download through the VPN but when I start up a game server on the machine no one can see it in ...
0
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1answer
55 views

Not able to open port on Ubuntu Server

root@server:~# ufw allow 83973/tcp Rules updated Rules updated (v6) root@server:~# sudo ufw status verbose Status: inactive root@server:~# sudo ufw enable Command may disrupt existing ssh connections. ...
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0answers
119 views

UFW, OpenVPN and P2P not working together

tl;dr I'm using UFW to to ensure all the connections from my computer are made only through my VPN and also to ensure if my VPN is down all connections are blocked. It's working, but I still have two ...
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0answers
24 views

Ubuntu UFW firewall and SSH after port changed

I changed by SSH port to a different port. I use Putty. I added the new port to ufw list: ufw allow port_number After I start the server, and try to connect, I get connection timeout. I use SSH ...
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0answers
290 views

IPTables/UFW Rules to Allow traffic from 2 or more local subnets to PC WHILE connected to a VPN with OpenVPN client

I really hope someone can help with this because im getting gray hair! If i have 3 different LAN subnets all already configured to "talk" to each other LAN1 = 192.168.7.0/24 LAN2 = 10.0.0.0/...
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1answer
74 views

How can I whitelist my Android device?

I have been digging and spending a lot of time setting up the most secure SSH environment possible on one of my servers. The last security measure that I want to take is to whitelist my phone on my ...
0
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1answer
261 views

ufw on rPi with OpenVPN

I've setup OpenVPN using the piVPN method on a raspberry pi. The installation has gone fine, I've configured the port forwarding on my router and I can connect successfully to the VPN from my android ...
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0answers
146 views

UFW: Deny all but ssh, openvpn on external interface, allow everything else

I'm setting up a server to contain multiple virtual machines which will be serving internet traffic and serve for internal use. I want to set up the server such that external access would only be ...
1
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1answer
37 views

ufw deny from IP ADDRESS still allows http access to website

I just typed these commands into bash on my ubuntu server ufw deny from 173.244.48.185 ufw reload ufw status And this gave this result To Action From -- ...
0
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1answer
557 views

Using ufw to block telnet from specified host

I'm new to ufw tool, I'm trying to block a specified host from requesting telnet while allowing other hosts on the network to do so. When I use this command: sudo ufw deny 23 The other host is ...
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0answers
161 views

I disabled ports with UFW on ubuntu but scans still show them as open

These are my UFW settings:- But these are my scan results:- So even if I have allowed only ssh and https for incommming connnections and all others should be disabled by default the 3rd party port ...
2
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1answer
612 views

Still unable to access Internet from Docker containers

Followed the https://stackoverflow.com/a/46266757 ("What is the best practice of docker + ufw under Ubuntu" answer by @mkubaczyk) guide to configure Docker with UFW properly but still unable to access ...
0
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1answer
188 views

UFW firewall difference between allow ip and allow port?

When using the UFW firewall app, what is the difference between allowing connections from to a port and allowing connection from an IP? If I allow connections from an IP does that mean that IP can ...
0
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1answer
70 views

Restricting UFW rule by protocol

I've been trying to create a specific rule to allow ssh and vnc from my local ip 10.1.1.230 but I keep getting errors. sudo ufw allow ssh from 10.1.1.230 sudo ufw allow from 10.1.1.230 to ...
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0answers
152 views

My ubuntu server firewall blocks the ip I am accessing it from

My ubuntu server firewall blocks the ip I am accessing it from. Here is iptables -L Chain INPUT (policy DROP) target prot opt source destination DROP all -- 192.168.1.1 ...
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0answers
90 views

Failure to start ufw after OpenVPN connection

I have currently configured my Ubuntu system to connect to an OpenVPN server on startup. This is done by placing a configuration file in the /etc/openvpn directory. Additionally, I would like to ...
1
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1answer
423 views

How to make secure linux server with firewall

I am installed the ufw firewall on linux server and allow necessary ports using ufw but Is there any other rules need to make secure server like DOS, Sync or any others(i've no idea about this) or Is ...
1
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1answer
345 views

ubuntu - block internet access to all applications except chosen few

I have been looking for a way to block all my applications from accessing the except for 1 or 2 chosen. I looked into Uncomplicated Firewall (ufw) and its respective Gui (gufw): but gufw doesn't ...
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0answers
318 views

OpenVPN - Fixing DNS leak using UFW

I am currently running OpenVPN on Fedora 24 and experiencing a typical DNS-leakage, since my /etc/resolv.conf entry is not changed after starting OpenVPN. To get rid of the DNS-leak, I am trying to ...
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2answers
404 views

Is it possible to restrict connection to database in Docker container at particular interface on Ubuntu 16?

I have MySQL database on a server (I use Percona in Docker container) with several network interfaces. My system is Ubuntu 16.04.2 LTS. ifconfig eth0 Link encap:... inet addr:95.*.*.*...
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0answers
116 views

How to identify which iptables rule has rejected specific connection (from log output)?

I have got a log readout showing connection attempts being rejected by iptables rule(s) (from the solution to this question), shown below: Feb 24 11:19:24 devmachine kernel: [17771118.615519] [UFW ...
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0answers
1k views

UFW Blocking FTP Access

I have installed UFW on debian and now my FTP server is not working whenever I connect to it using a client, it allows me to log in and lists my home directory, but whenever I try to navigate ...
3
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0answers
467 views

What docker stack layout for nginx, ufw, fail2ban, and private services

I have an unraid server running some dockerized services (eg emby & seafile) that offer web interfaces which now need to be opened up in order to be accessible from outside the LAN. Never opened ...
0
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1answer
2k views

ubuntu 16.04 trying to open port 8443 not working

i need to open port 8443 in OS ubuntu 16.04 but nothing is working first i tried to do a scan port using Nmap: RESULT : Discovered open port 139/tcp on 127.0.0.1 Discovered open port 445/tcp on ...
0
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1answer
97 views

What is the effects of adding “Listen 443” to “sshd_config”

I was following this tutorial tutorial where i added this line Listen 443 to sshd_config without changing anything else, now i can no longer connect to the default 22 port
3
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2answers
3k views

How to make a VPN kill-switch for mac OS X

What I wanna do is to have the internet connection disabled completely when the VPN connection goes down. I am connecting to my VPN (privatevpn.com) through Viscosity. I have tried everything in the ...
1
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0answers
331 views

DDClient with OpenVPN

I'm at a complete loss trying to figure out how to obtain my local public IP address, rather than my VPN's public IP address as my VPN doesn't seem to allow incoming traffic. Basically, I need ...
0
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1answer
846 views

how to allow ssh connections to server only from local UFW

I have Ubuntu 16.04.1 x64 droplet on digital ocean. I have set up open.vpn and ufw on it. UFW blocks all ssh connections. I would like it to allow ssh connections from computers which use this server ...
0
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1answer
138 views

Command to check IPV6=yes in ufw is in effect

We can set IPV6=yes by editing /etc/default/ufw to support monitoring of ipv6 packet transfer. But it will take effect only after ufw is disabled and enabled or reloaded. The question is Is there a ...
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1answer
308 views

What are the basic commands for ufw firewall in Ubuntu?

I want to setup ufw firewall in ubuntu. Please list some basic commands that I need to learn to operate it via termianl.
3
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1answer
2k views

How do I kill existing network connections on Linux?

I've been working on a project that is nearly complete: to be able to kill my children's internet connections at the touch of a button. I've implemented part of the solution by basically calling: ...
0
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1answer
62 views

Has Kubuntu 15.10 been hacked?

Can someone tell me what this message means please? [system] Rejected send message, 10 matched rules; type="method_return", sender=":1.19" (uid=0 pid=1183 comm="/usr/sbin/dnsmasq --no-resolv --keep-...
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0answers
399 views

What exactly are the security implications of ufw DEFAULT_FORWARD_POLICY “ACCEPT”?

I found this question asked on Serverfault, but the answer just provided alternatives instead of actually detailing the implications. I had to set DEFAULT_FORWARD_POLICY to "ACCEPT" to be able to ...
3
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2answers
2k views

Ubuntu 14.04: enabled ufw and forgot to allow ssh

Last night I did a most annoying mistake. On a Ubuntu 14.04 server I enables ufw and forgot to allow ssh. Then I logged off. Naturally I am now locked out with ssh. Fortunately my hoster provides a ...
0
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1answer
582 views

SSH fails to connect on private interface over IPSec tunnel

I have Client and Server in different locations connected via an IPSec tunnel, if I try to ssh from Client to Server over the internet everything works fine. I have tried from several Linux and Cygwin ...
1
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1answer
450 views

pptp port 1723 unreachable

I'm trying to setup a pptp VPN on my server, but for some reasons the server is not responding to me. on the server I have: $ sudo netstat -alpn | grep :1723 tcp 0 0 0.0.0.0:1723 ...
3
votes
1answer
2k views

Block applications using UFW

I am using Ubuntu 14.04 desktop. I want to block certain applications from accessing internet and allow some. Can this be done using UFW ? If yes, how ? If no, can it be done by any other method ? I ...
1
vote
1answer
849 views

How to disable rate limit on SSH connections in UFW?

I've got a dev server to which I constantly sync my code using rsync. To secure the dev server a bit more I now activated UFW, which seems to work fine. The problem is that it works a bit too well, ...
0
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0answers
430 views

Allow port 1352 via UFW and Squid

Our server runs UFW and Squid (along with SquidGuard). All the systems in our LAN connect to the Internet via this server. UFW seems to allow port 1352. Squid also seems to allow connections on port ...
1
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0answers
574 views

Limit connections per second with iptables/ufw

How can I tweak the following entries to allow more requests per second? Maximum hitcount is 20 if you do not edit some other config files. The entry of my /etc/ufw/before.rules file -A ufw-before-...
1
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2answers
481 views

Set block time with iptables

I have the following rules in ufw, for iptables: -A ufw-user-input -p tcp --dport 80 -m state --state NEW -m recent --set -A ufw-user-input -p tcp --dport 80 -m state --state NEW -m recent --update --...
1
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1answer
467 views

confusing INPUT,OUTPUT iptables rules

Following is my iptables rules in Ubuntu. ╰─$ sudo iptables -S -P INPUT ACCEPT -P FORWARD DROP -P OUTPUT ACCEPT -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT -A ...
6
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2answers
6k views

Using Raspberry Pi as IPv6 router for network

I've succeeded in setting up IPv6 for my Raspberry Pi with tunnelbroker.net. However, I would like to share the /64 I got amongst the other devices in my network. The router of the network is a Virgin ...
10
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5answers
33k views

Is it possible to put UFW on CentOS?

If so, how would I do it? If not, is there an easier way to set some basic rules on CentOS other than iptables? I'm more of an app developer and less of a sys admin.
0
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1answer
2k views

UFW default rules… where are they?

In the tutorial on UFW here https://help.ubuntu.com/community/UFW it says that UFW uses the default rules if enabled and not configured. I checked the folder: /etc/ufw/ and the files I found there ...
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2answers
1k views

With ufw, how do I limit SSH from outside, and not from inside?

Using UFW, limiting connection attempts for things like SSH is real easy: # ufw limit SSH However, I'd like to limit only the public-facing interface, not the LAN interface. This command does it ...