a technological barrier designed to prevent unauthorized or unwanted communications between computer networks or hosts

learn more… | top users | synonyms

0
votes
0answers
17 views

Ubuntu ufw blocking connection from allowed port

I have a strange bug, some of my visitor getting blocked somehow, somewhere. It is very strange. For example, it can connect to our database, but after he is trying to access the webpage, all the ...
0
votes
0answers
19 views

What could block a port on a fresh install of 16.04?

I need to share port 18090 on my local are network, however something is blocking it. netstat -ltn shows that 127.0.0.1:18090 is listening. I have issued both sudo ufw disable and sudo /etc/init.d/...
1
vote
1answer
3k views

UFW not enabled at startup

I have enabled the UFW in terminal using "sudo ufw enable" ... But, UFW does not appear to start when the computer starts. After the computer starts, I check the status of the UFW using "sudo ufw ...
0
votes
0answers
18 views

firewall - openvpn issue

I've been trying for days.. to get openvpn to LAN working I can ping both directions but can't connect to any machine on lan. So my question, what's wrong with my firewall setup?? openvpn and ...
0
votes
1answer
4k views

How to make ubuntu gateway?

i am new on Ubuntu. i want to make a gateway. i have some 25 systems and switch but i don't have any server. i want to setup a system as a gateway system and want to make a firewall. i want that ...
-1
votes
0answers
26 views

Ubuntu Server 16.04 as a Router & Firewall [duplicate]

what should I do? I can't save and exit with :wq or ctl+O and ctl+X
4
votes
1answer
5k views

UFW for OpenVPN

I want to configure ufw (uncomplicated firewall) for OpenVPN. Connections are only allowed through OpenVPN. Everything else should be blocked. So if OpenVPN is disconnected -> no internet! I found ...
0
votes
3answers
3k views

How do I with ufw deny all outgoing ports excepting the ones I need?

I did the following: ufw default deny outgoing, sudo ufw allow out 80 which I thought would let me use the Internet but didn't can y'all help? Also are there any other ports used by Ubuntu for which ...
1
vote
0answers
54 views

UFW setup for OpenVPN server

I set up OpenVPN server on one Ubuntu machine and I am connecting to it via another Ubuntu machine. However, the VPN works only when the server firewall (ufw) is disabled. That is I can connect when ...
1
vote
1answer
19 views

iptables rule traverse order

Here is partial output of my iptables: Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 22866 ...
0
votes
0answers
23 views

How do I open ports for Asterisk and SIP?

How do I know whether port 5060, for SIP, is open on localhost? thufir@mordor:~$ thufir@mordor:~$ nmap localhost Starting Nmap 6.47 ( http://nmap.org ) at 2016-06-29 23:09 PDT Nmap scan report for ...
0
votes
0answers
49 views

nmap scan on Ubuntu results in odd result

1. I ran an nmap scan on my system and this was the out put. hobbit@hobbit-OptiPlex-GX520:~$ nmap -v sU sT 127.0.0.1 Starting Nmap 7.01 ( https://nmap.org ) at 2016-06-25 20:08 IST Initiating Ping ...
0
votes
0answers
26 views

Access to white IP when VLAN is not default

I have Ubuntu 16.04. VLANs in NetworkManager. As per picture , I have 1 Eth interface and 3 VLANs, each with it's own GW. The default VLAN at the time is 5 (NAT). The other VLANs have white IPs ...
0
votes
0answers
12 views

How to make a SSH connection if my proxy server doesn't allow connections at port 22?

My college internet uses a proxy server to provide internet to the students with a firewall which only allows connections at port 443 and port 80 and blocks others. I want to know is there anyway I ...
0
votes
0answers
24 views

Sharing through Iptables stopped working

I have a server connected with the internet and the local network. The configurations are: eth0 - 192.168.10.1 eth1 - 192.168.0.6 (Internet) When I wanted to share the internet with other computers,...
0
votes
0answers
46 views

SoftEther VPN Server returning error. “Error occurred. (Error code: 1) Connection to the server failed. Check network connection …”

This topic had already been discussed in SoftEther VPN Server can't connect during set up. But cannot find the solution here in my case. Tried commenting still not received a resolution. So ...
2
votes
5answers
1k views

Blocking Remote Login

Last night, I was shutting down my server and I saw a message asking if I wanted to shut down a "pts/0" session. Odd, I thought. So I logged back in and did a finger and saw that there was someone ...
0
votes
1answer
29 views

Scanner / printer firewall

My firewall is blocking the scanner from working but the printer works fine. Obviously when i turn off the firewall they both work. I can't figure out how to configure the firewall to allow the ...
3
votes
1answer
33 views

Redirect iptables logging to another logfile

I have followed the recipe by @Gilles in this answer. I succeeded, but the problem is that the iptables logging now goes into 3 log files, syslog, kern.log and iptables.log. Ideally, I want the ...
0
votes
0answers
16 views

Prevent Outbound IP Address spoof

We have multiple computers running Ubuntu Desktop, all connected to same Router. Using UFW firewall, all inbound and outbound ports are blocked on these Desktops, except for only one outbound port (...
0
votes
0answers
25 views

UFW doesn't do anything

I have an Intel nuc running Ubuntu Server with UFW enabled and im trying to block port 8112 however i can still reach it from outside my network. I have tried the following sudo ufw reset sudo ufw ...
0
votes
0answers
32 views

figthing with firewall configuration and samsung network printer in Networking & Wireless

I've configured my Samsung SCX-3205W printer and scanner in Ubuntu 15.10 and everything worked fine until I've turned on firewall. After some forums reading and some fighting I've discovered that it's ...
4
votes
1answer
3k views

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 ...
0
votes
0answers
43 views

UFW issue in Ubuntu LTS 14.04

While executing shell command ufw status && ufw enable - I am getting the error message below: iptables v1.6.0: can't initialize iptables table `filter': Permission denied (you must be ...
2
votes
1answer
2k views

ERROR: problem running ufw-init

I tried setting up ufw on my remote Ubuntu 14.04 server so i installed it and allowed ssh with the command sudo ufw allow ssh after that I tried to enable ufw but I get the following error: ERROR:...
0
votes
0answers
25 views

Allowing access from only a specific IP does not work

I would like to access port 22 (ssh) of a computer whose OS is Xubuntu 15 from a specific laptop with Windows 10 and external IP x.x.x.x using Putty via Internet (i.e., these computers are not in the ...
0
votes
0answers
13 views

Motor Control with Firewall Application

I am working on a project which calls for 4 axis coordinated motion control along with a multi port firewall all in one. In reading through the forum it appears that the Snappy Core would be a good ...
0
votes
0answers
29 views

How to add ip to firewall wineHQ

I used Wine HQ 1.9.12 and I have problem with settings from firewall. I want ask about firewall because I must add ip allowed. This is my allowed connection. How can I add new ip ?
0
votes
0answers
42 views

How to use iptables to prevent repeated attacks on port 80?

There a is massive attack on port 80 on my Server i try to use iptable This way to banned attackers iptables -A INPUT -s 212.252.96.128 -j DROP but there are too many IPs attacking how to prevent ...
3
votes
0answers
31 views

UFW Blocking Legitimate Traffic

I am currently getting this kind of message in the UFW and sys logs: xxx kernel: [4962636.572484] [UFW BLOCK] IN=et0 OUT= MAC= SRC=xxx.xxx.xxx.xxx DST=xxx.xxx.xxx.xxx LEN=52 TOS=0x00 PREC=0x00 TTL=52 ...
1
vote
2answers
97 views

How to Block a range of IP address with UFW

I am trying to block a range of IP address on my Ubuntu 16.04LTS server from a specific country, i.e. China, Iran, etc. I was hoping to find a script or something I could run to easily make a ...
0
votes
3answers
10k views

Open port 80 on Ubuntu server

I'm just starting out in ubuntu/linux, and have some trouble opening port 80 for incoming connections. I ran the sudo ufw allow80/tcp command, and when I run sudo ufw status the result looks like ...
0
votes
0answers
35 views

redirect traffic from server 1 to server 2 on specific ports

I am trying to redirect traffic from server 1 on IP A to server 2 on specific ports and IPs. i am using this rule as an e.g. - iptables -t nat -A PREROUTING -s 192.168.1.1 -p tcp --dport 1111 -j ...
0
votes
0answers
39 views

What ports do I need to open for NFS on UFW?

I currently have ports 111, 1110, 2049 and 4045 open and I am having an issue connecting to my kodi clients. When I disable UFW, everything connects just fine. I have googled and haven't found any ...
1
vote
0answers
133 views

Firewall configurator not opening after upgrade to 16.04

after upgrading to 16.04 the firewall configurator is not showing up any more. The firewall itself (UFW) seems to be running as: sudo ufw status returns active and my rules. running the GUI from ...
0
votes
0answers
40 views

How do I block traffic from certain VPN clients?

I have a Ubuntu 14.04 server setup as a VPN Server. I have several Ubuntu Desktop machines which connect to the VPN server using PPTP - all works fine. My problem is that I need the VPN clients to ...
1
vote
1answer
71 views

GUFW does not open for configuration in 16.04

Yes I have a dell Inspiron 15 3552 notebook, Intel Pentium N3700 with 4GB memory. Every time I try to open the blue and white icon, the password window appears. this I enter with no problem but then ...
0
votes
1answer
19 views

Create a permanent rule for iptables in Ubuntu

In order to establish connection with my Ubuntu server I have to add the following rule to iptables: sudo iptables -A INPUT -p tcp --dport 80 -j ACCEPT Everything is working until I reboot the ...
0
votes
0answers
15 views

GUFW limit access to websites

Do anyone know how I can limit access to certain websites during specific hours of the day using GUFW? If GUFW do not have this ability, what can I use instead to achieve this function?
0
votes
0answers
33 views

Firewall with ability to block manually temorarily ip addresses, ports?

I have made a DDoS detection system that gives me info about malicious IP addresses and ports need to be blocked. Does anyone knows good solution of firewall, allowing me to do that. More automated ...
0
votes
0answers
27 views

Ubuntu 14.04.4 LTS: Firewall - block countries

I'm having trouble with my VPS. IPs from both China and Russia is trying to brute-force my VPS (not like there's anything interesting), and it's annoying. I'd like to ask, if there's any way I can ...
1
vote
1answer
55 views

Port forwarding/bypass firewall

I have two servers located at two different places: Ubuntu Server (MySQL) Ubuntu Server (Tomcat) The problem here is that the Tomcat server cant send data to the mySQL server over port 7878 because ...
1
vote
0answers
37 views

Transmission not downloading due to ufw

I set up ufw and it works nicely with every other service I have but Transmission is a mystery to me. It seems to start up and use different ports every time. Currently I've managed to get it to work (...
1
vote
1answer
64 views

Iptables rules slow down loggining in via SSH

I am trying to build some basic iptables rules for my VDS: iptables -A INPUT -p tcp --dport ssh -j ACCEPT iptables -A INPUT -p tcp --dport 80 -j ACCEPT iptables -A INPUT -p tcp --dport 443 -j ACCEPT ...
0
votes
1answer
46 views

VNC Server Missing and UFW disabled and iptables empty after update?

I have an Ubuntu 12.04 computer in the other room that I remote into using Remmina Remote Desktop Client and VNC on another Ubuntu 12.04 desktop. It worked about 1 month ago. Now Remmina hangs at "...
1
vote
2answers
34 views

Is there a way to whitlist ip's and block everything else

So i'm running ubuntu on my vps. But the problem is that i have kids trying to figure out the password of the FTP connection and the VNC connection. (with succes). Now i want to ask is there a way to ...
1
vote
1answer
89 views

How can I block outgoing network traffic, based on useragent?

What would be the simplest method to ensure that all outgoing traffic matching specific user agent is blocked? To avoid XY problem: I want to disable “A new version of Sublime Text is available, ...
0
votes
0answers
28 views

Bluetooth connect changes iptables behaviour

I have a very strange situation where a bluetooth connection seems to change the behavior of the iptables firewall. Let met start from the beginning: I have a Onkyo stereo amplifier with a bluetooth ...
0
votes
1answer
108 views

IPTables: Block incoming traffic connection to your IP address of your virtual machine

Host OS: Ubuntu 14.04 Guest OS: Ubuntu 14.04 (Virtual Box) I want to block incoming traffic connection from Virtual machine with IPTables. I have searched, One solution I found is static IP for ...
0
votes
0answers
58 views

iptables for setting up a transparent proxy

I have set up ubuntu server 14.04 on VirtualBox with two network interfaces. auto eth0 iface eth0 inet static address 192.168.1.5 netmask 255.255.255.0 gateway 192.168.1.1 dns-...