Uncomplicated Firewall is a firewall configuration tool for Linux. It acts as a frontend to iptables. Originally designed for Ubuntu, it is available on many Linux distributions.

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21
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Where does UFW (uncomplicated firewall) save command-line rules to?

You add a rule like this: ufw allow 22/tcp The rule is saved, and is applied even after reboot. But it's not written anywhere in /etc/ufw. Where is it saved to? (Ubuntu, using ufw as pre-installed.)...
16
votes
1answer
20k views

Can I use ufw to setup a port forward?

Im currently using ufw to enforce some basic firewall rules. Is it possible to also use ufw to do port forwarding? Specifically im wanting to forward incoming traffic to my server (same machine ...
15
votes
3answers
9k views

Rate limiting with UFW: setting limits

UFW's man page mentions that it can setup iptables rate limiting for me: ufw supports connection rate limiting, which is useful for protecting against brute-force login attacks. ufw ...
14
votes
3answers
1k views

Debugging iptables and common firewall pitfalls?

This is a proposed Canonical Question about understanding and debugging the software firewall on Linux systems. In response to EEAA's answer and @Shog's comment that we need a suitable canonical ...
13
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2answers
19k views

Ubuntu ufw: set a rule on a per interface basis

I want to create a rule that allows anyone on eth1 to access port 80. Can UFW do this or should I go back to using Shorewall? To clarify: this is a capabilties question, can ufw handle interfaces as ...
12
votes
1answer
9k views

Where are the logs for ufw located on Ubuntu Server?

I have an Ubuntu server where I am blocking some IPs with ufw. I enabled logging, but I don't know where to find the logs. Where might the logs be or why might ufw not be logging?
8
votes
1answer
4k views

Copy UFW rules between servers

I'm doing a hardware refresh on a my Colo, I just need to copy my UFW rules from my old server to my new server. I dont seem to be able to get them copy all the active rules from my old server to my ...
7
votes
1answer
2k views

UFW logs blocked request on open port, what am I missing?

Nov 29 15:17:15 hostname kernel: [397768.554884] [UFW BLOCK] IN=eth0 OUT= MAC=[mac] SRC=[ip] DST=[ip] LEN=52 TOS=0x00 PREC=0x00 TTL=52 ID=17050 PROTO=TCP SPT=56152 DPT=80 WINDOW=65535 RES=0x00 ACK ...
7
votes
1answer
3k views

Ubuntu: How to add an iptables rule that UFW can't create

UFW is working really well for me except in the cases where it doesn't... I want to be able to add another rule manually that will be applied on boot? where should i put this rule? how should I ...
6
votes
2answers
19k views

opening port 80 on Ubuntu AWS

I'm running a tomcat server on an ubuntu machine hosted in an AWS instance. I can reach the server via public_ip:8080 but when i change the listening port on server.xml from 8080 to 80 connection is ...
6
votes
1answer
3k views

Should I be using iptables or ufw?

I know of iptables. I know of ufw. I've been using ufw in the past just because it's easier to setup and use. However, which one should I be using? Is iptables more secure? Is ufw more stable? I ...
6
votes
1answer
944 views

Security implications of setting UFW default_forward_policy to accept?

The docker manual (http://docs.docker.com/installation/ubuntulinux/#docker-and-ufw) states that it's nescessary to set UFWs DEFAULT_FORWARD_POLICY to "ACCEPT" so docker containers can reach each other....
5
votes
1answer
358 views

What's the effect of iptables/ufw deny filters on server load?

I'm wondering how scalable it is to add IP addresses or subranges I want to block into ufw. E.g., I do this whenever I discover a particularly bad bot or server farm. As my list grows, I wonder how ...
5
votes
1answer
99 views

Do I need to open any port for NTP synchronization to work if both outgoing and incoming are blocked on ufw?

One of my production servers, UFW configuration is as follows: Status: active Logging: on (low) Default: deny (incoming), **deny (outgoing)**, disabled (routed) New profiles: skip To ...
5
votes
4answers
3k views

ufw blocking apt and dns

I installed ufw on my Debian system like the following: # aptitude install ufw # ufw limit 22 # ufw allow 80 # ufw allow 443 # ufw enable # ufw status verbose Status: active Logging: on (low) Default:...
4
votes
2answers
6k views

How to make netstat on Linux only show OUTBOUND tcp connections?

My ubuntu server is infected and there is a process making a bunch of HTTP requests to a bunch of websites (sucks!). I have added the following to my firewall (UFW): sudo ufw deny out proto tcp to ...
4
votes
2answers
4k views

UFW Firewall Rules ordering?

I have the following rules on our server within UFW: To Action From -- ------ ---- 22 ALLOW 217.22.12.111 22 ...
4
votes
1answer
1k views

Cannot loopback to localhost php gateway causing nginx to timeout while setting up firewall with ufw

I'm setting up ufw for the first time. Using Ubuntu 10.04 LTS on an OpenVZ VPN and have the following rules: sudo ufw allow 22/tcp sudo ufw allow 25/tcp sudo ufw allow 53 sudo ufw allow 80 sudo ufw ...
4
votes
1answer
834 views

How to block an attack on Wordpress using UFW on Ubuntu server?

On ny Ubuntu 14 box I have weird activity looking like attack on Wordpress page. Apache log shows a lot's of this: 191.96.249.54 - - [25/May/2016:00:46:57 +0200] "POST /xmlrpc.php HTTP/1.0" 500 585 "-...
4
votes
2answers
7k views

Opening port 5432 on ubuntu

I am trying to open port 5432 on ubuntu using ufw using sudo ufw allow 5432/tcp I then use nmap to see if port 5432 was opened and i get this: root@domain:~# sudo nmap -sS -O 127.0.0.1 Starting ...
4
votes
3answers
2k views

Disable connection tracking with UFW for port 80

During load testing my server is dropping packets due to "connection tracking" way before it's running out of resources. I'm using Ubuntu Jaunty with ufw. In my syslog I get: ip_conntrack: table full,...
4
votes
2answers
4k views

Correctly setting up UFW on Ubuntu Server 10 LTS which has Nginx, FastCGI and MySQL?

I'm wanting to get my firewall on my new webserver to be as secure as it needs to be. After I did research for iptables, I came across UFW (Uncomplicated FireWall). This looks like a better way for me ...
4
votes
0answers
3k views

ufw deny all incoming and outgoing not working! [closed]

I'm sure I'm doing something wrong. I'm expecting my current rules of "denying all incoming/outgoing" to cripple anything network related, but it's not. First, I did: sudo ufw default deny incoming ...
3
votes
1answer
10k views

UFW on Ubuntu to Allow All Traffic on LAN

I want to allow all LAN traffic to my Ubuntu server. I have read the documentation and see the command, but when I try to edit the command for my IP range I get an error. How can I allow all traffic ...
3
votes
2answers
4k views

Turning on UFW stops my e-mail client functioning (both imap and smtp) even though they are allowed?

I am using ubuntu 10.04 on a VPS. Without enabling UFW everythign works fine - imap using port 143. And sends emails using smtp port 587. However, when I turn on UFW a lot of problems are ...
3
votes
2answers
347 views

Which UFW messages can logcheck safely ignore?

Logcheck currently sends lots of emails with messages like this Jun 6 19:31:44 <hostname> kernel: [UFW BLOCK] IN=eth0 OUT= MAC=<mac-address> SRC=<source-ip> DST=<destination-ip&...
3
votes
1answer
3k views

Depend on a resource only if it exists in Puppet

I have a class for enabling firewall on nodes (using ufw, in Ubuntu): class ufw { package { ["ufw"]: ensure => latest } exec { "enable-firewall": command => "/usr/bin/yes | /usr/...
3
votes
1answer
31 views

UFW - Rules by Service Versus Port and Protocol

What is the difference between creating allow/deny rules via a service versus a port and protocol? For example: ufw allow ssh versus ufw allow 22/tcp or even, ufw allow ssh/tcp. Which is the 1) ...
3
votes
1answer
285 views

ufw cancel port forward

On Ubuntu server 14.04, I enabled ufw port forwarding from 80 to 8181 (tcp) by using the checked answer on Can I use ufw to setup a port forward? Finally I'd rather proxy http request using apache2 ...
3
votes
1answer
711 views

Ubuntu Server 12.04: How does one configure the firewall during installation?

I'm following instructions to automate the installation of Ubuntu Server 12.04 using kickstart. It works well for automatically partitioning the drives, selecting languages etc. However, it doesn't ...
3
votes
1answer
1k views

How to place a virtual machine in DMZ?

I have an Ubuntu 12.04 server running few virtual machines with KVM. I would like to expose some of these virtual machines on the internet, to make it possible for customers to test the products we'...
3
votes
1answer
1k views

UFW/IPTables: how to securely allow authenticated git access with github

This is how I setup my iptables with UFW: sudo ufw default deny incoming (deny all incoming) sudo ufw default deny outgoing (deny all outgoing) sudo ufw allow out 53 (accept outgoing DNS traffic, ...
3
votes
1answer
42 views

enabling ufw disables some of the settings in sysctl.conf

When I add rules to ufw and then enable it, some of my settings in sysctl.conf become void so I have to do sysctl -p after doing ufw enable. So for example one of my settings in sysctl.conf is to not ...
3
votes
1answer
381 views

UFW: Disable logging of blocks due to optional FIN/ACK message being received

I've recently built a server and decided to use UFW for the first time. I was investigating a possible connection issue (turns out it was their end) but I noticed that the logs are full of entries ...
2
votes
2answers
2k views

UFW/IPTables: after setting default outgoing deny, and port 80 outgoing allow, curl still doesn't work

With UFW, I disabled all outgoing and ingoing traffic by default. However, I do allow port 80 in and out: sudo ufw default deny incoming (deny all incoming) sudo ufw default deny outgoing (deny all ...
2
votes
2answers
616 views

How to show the current configuration of iptables with ufw?

This is what I get when I try to see the current iptables configuration: nes@sw-eng:~$ sudo ufw show ERROR: Unsupported action 'show' So, what else is there?
2
votes
1answer
2k views

UFW blocking port 80 when it should not

I have these rules in UFW (default deny): 80 ALLOW 10.0.0.0/8 443 ALLOW 10.0.0.0/8 80 DENY Anywhere 443 ...
2
votes
1answer
449 views

Recommended ufw port configuration to secure tomcat web-application ubuntu server?

Assuming an ubuntu server operating web applications on Tomcat (with redirection from apache 80 to 8080). What is the recommended port configuration to secure the server? Thanks. P.S.: I would like ...
2
votes
1answer
103 views

How to disable UFW ubuntu externally?

i am using amazon EC2, i enabled UFW in my server and without adding any other rule i logged out. now since there was no rule specified, i am not able to login to ssh and because of it even my website ...
2
votes
1answer
1k views

UFW - can I add a domain?

This will work fro the docs: sudo ufw allow proto tcp from 192.168.0.2 to any port 22 But..will this work? sudo ufw allow proto tcp from foo.bar.com to any port 22 I am using ubuntu 12.04
2
votes
1answer
230 views

In ufw is there any way to disable logging for a particular rule?

I am using UFW with a default logging policy of "low". I would like to keep this logging on for the default deny action, but disable it for a particular IP address only. So I'd like to create one ...
2
votes
1answer
275 views

UFW rules in place and enabled yet traffic still allowed

I have UFW configured to try and block some unwanted IPs and associated requests. #ufw status |less Status: active To Action From -- ------ -...
2
votes
1answer
596 views

Can ufw on a kvm host restrict traffic to guests?

I've set up a number of guests running on kvm on Ubuntu. Network access for the guests is via network bridge with br0 sitting on top of eth0. I have ufw running on the host machine and this is ...
2
votes
1answer
1k views

setting up ufw for a website, I want to to disallow everything except ssh, e-mail, and http

I have read the basic instructions here: https://help.ubuntu.com/community/UFW I want to sudo ufw default deny and then sudo ufw allow ssh sudo ufw allow smtp sudo ufw allow www sudo ufw allow ...
2
votes
2answers
976 views

How to utilize UFW blocking published ports from docker

Might seem a silly question but i'm trying to get the following to work: I have a correctly configured UFW for only allowing certain source IPs access to my local service after migrating this ...
2
votes
0answers
488 views

Using ufw on OpenVZ-based VPSes

I'm facing with a problem to set up ufw on Ubuntu 12.04 running on an OpenVZ-based VPS. I know there is limitations for ufw. I googled a bunch of articles how to resolve the issue (like: http://blog....
2
votes
1answer
178 views

Cannot directly reject traffic on port 25

My server is running Ubuntu 10.04.4 LTS and I want to reject traffic to port 25. The goal is this: $ telnet {ip} 25 Trying {ip}... telnet: connect to address {ip}: Connection refused telnet: Unable ...
1
vote
3answers
713 views

Is this a security breach?

I have a server running Ubuntu 10.04LTS (I know it is too old), which over the last couple of weeks has on occasion been unresponsive to network traffic, and needed a hard reset first thing in the ...
1
vote
4answers
3k views

How To Set iptables log rules for PSAD with UFW?

For PSAD to work, I need to add the following iptables rules and enable packet logging : iptables -A INPUT -j LOG iptables -A FORWARD -j LOG ip6tables -A INPUT -j LOG ip6tables -A FORWARD -j LOG I ...
1
vote
3answers
751 views

Locking down my Ubuntu server with UFW [duplicate]

I'm using Ubuntu 12.04 on an Amazon EC2 instance and new to the sysadmin side of things. I'm working on a little project of my own and I'm already starting to get targeted by bots (at least I hope ...