0
votes
1answer
42 views

How do I test my firewall rules?

I've setup some rules in ufw and I've turned it on. Now I want to ensure my rules actually block traffic. However, when running nmap -PN -p <my_port> <ip> from my local workstation it ...
0
votes
1answer
85 views

Why does the DOCKER chain show in `ufw raw` but not using `iptables -L`

If I run sudo ufw raw, I can see an iptables chain called 'DOCKER': Chain DOCKER (2 references) pkts bytes target prot opt in out source destination 0 0 DNAT ...
0
votes
1answer
69 views

Iptables/ufw - blocking ports when using nat

I use NAT to move requests from external ports to an internal ip address and port hosted with proxmox. Something like this: iptables -t nat -A PREROUTING -i vmbr0 -p tcp --dport 8000 -j DNAT --to ...
1
vote
1answer
55 views

Something (but not iptables) mysteriously redirects network traffic - how to diagnose?

Summary There is a virtualbox host (1.1.1.5) and a routed guest (1.1.1.6). Something redirects any traffic on port 25 with the guest, whether ingoing or outgoing, to 1.1.1.5 port 2525 and I cannot ...
0
votes
1answer
33 views

ufw instead of pure iptables

I am running an Ubuntu server VPS that several people with varying networking skills need to manage. Currently the server is protected by iptables. I am considering using ufw to gain simplicity. What ...
1
vote
0answers
42 views

strongswan packet get natted when ufw is enabled

I'm using strongswan 4.6.4 to connect road warriors to my server (ubuntu 13.10), which is natted behind a firewall. left=%defaultroute leftsubnet=10.10.1.0/24 right=%any ...
0
votes
1answer
200 views

Locked myself out of SSH with UFW

I had my server set up to accept SSH connections on port 21966, I followed some steps to configure ufw however it has now locked me out of all SSH access on any port! I've been able to boot my ...
1
vote
1answer
145 views

iptables DNAT port forward to another machine on LAN

I am trying to implement iptables forwarding rules in order to internally redirect packets coming through a specific port. My machine is running under the distribution Ubuntu Server 12.04.3, with UFW ...
1
vote
0answers
161 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: ...
0
votes
1answer
68 views

Limit HTTP method on ubuntu 12.04 server

For starters, this is not a web server. I would like to allow or deny HTTP methods on various ports on the server itself. Ideally could write rules like UFW only extended to include the HTTP method ...
0
votes
1answer
154 views

Adding a custom SSH port to Ubuntu 12.04 LTS through UFW

I am trying to configure a Ubuntu 12.04 based VPS and I have changed my ssh port from 22 to 803 and everything worked fine. After this I've installed UFW and now I can't login using SSH. Before I ...
1
vote
1answer
61 views

Is there an iptables-apply equivalent for ufw

I just came upon iptables-apply, which applies an iptables ruleset and lets the user confirm that everything is working correctly before finally committing the changes. If the user does not confirm ...
1
vote
0answers
96 views

Strange dropped packets coming from port 8888 and with ACK or ACK+PSH set

Background During an incident on a small privative network (1 router/FW + 1 server) my server got accidentally exposed to the internet. Fortunately it was protected by it's own UFW to allow only 1 ...
1
vote
1answer
248 views

Amazon EC2 Servers with syslog-ng communication

I have 3 Amazon EC instances with ubuntu 12.04 Production Server (LAMP Server w/o MYSQL, syslog-ng client) Development Server (LAMP w/ MYSQL, syslog-ng client) Logging Server (syslog-ng Server) I ...
0
votes
1answer
119 views

Translating IPTables rule to UFW

we are using an Ubuntu 12.04 x64 LTS VPS. Firewall being used is UFW. I have setup a Varnish + LEMP setup. along with other things, including an Openswan IPSEC VPN from our office to the VPS data ...
1
vote
3answers
285 views

Testing the limits of UFW with thousands of deny blocks

Here's the deal: I have a persistent Chinese botnet that spams my forum (running on an Ubuntu 12.04.2 server on nginx, etc). I've been using UFW (Ubuntu's "Uncomplicated FireWall") for managing the ...
5
votes
3answers
3k views

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 ...
2
votes
1answer
132 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 ...
-2
votes
1answer
580 views

Restrict traffic to local network and VPN using ufw or iptables

I want to restrict all traffic from my ubuntu-machine to come or go from the local network (eth0) or from or to my VPN (tun0). It should be possible to connect the router in the local network but not ...
0
votes
2answers
1k 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
2answers
1k views

Cant forward port 443 to 8443 without allowing 8443 on ufw

I configured port forwarding through iptables and ufw. But there is something I do not understand, I just cant get iptables to forward port 443 to 8443 without allowing port 8443 on UFW. I want port ...
4
votes
1answer
171 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 ...
1
vote
2answers
453 views

Firewall blocking some strange communications from source-port 22 to over-seas ip addresses. Should I be concerned?

I'm responsible for a server that serves a single service (ssh) over the internet via port-forwarding through a firewall. The ssh service login is limited to encryption-key only (no passwords ...
3
votes
1answer
723 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, ...
0
votes
1answer
906 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
478 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?
4
votes
2answers
5k 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 ...
1
vote
0answers
2k views

ufw deny all incoming and outgoing not working!

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 ...
7
votes
1answer
10k 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 ...
0
votes
2answers
187 views

IPTables rules re-appearing

Folks, I created two machines on SoftLayer's cloud. The machines are Ubuntu 10.4 64 bit, minimal config. I am running into a really strange problem that I have no idea where it is coming from. The ...
3
votes
1answer
1k 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 ...
2
votes
1answer
1k 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 ...
1
vote
3answers
584 views

Upgrading to ufw on Ubuntu 9.04

I've recently upgrade my Ubuntu server install to 9.04. I'd like to install and use ufw. Is there a way to import my existing iptables into ufw? I'm worried about switching it on, and having all my ...