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

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270 views

How to connect remotely to WD Book Live Duo using nfs?

Connection in local network works perfect. I use nfs://192.168.0.10/nfs to connect locally. If I connect from internet I use static IP: nfs://xxx.xxx.xxx.xxx/nfs In this case it doesn't work and ...
2
votes
1answer
3k views

Forwarding ports with iptables not working?

I have an ubuntu server (14.04.1) which is asking as a router for my network. It has an internet facing interface, eth0, and a second interface, eth1, for connecting to my 10.0.0.0 network. I am ...
0
votes
1answer
125 views

How to perform detail packet capture on Ubuntu firewall?

I've routed internet traffic of my other systems on this ubuntu linux system where I have configured packet forwarding. but still I am unable to get internet on other systems. Hence I want to ...
1
vote
2answers
129 views

How do I use Juju local with a firewall?

While using ufw (Uncomplicated FireWall) and I noticed that the local juju machines were stuck in a pending state. $ juju status environment: local machines: "0": agent-state: started agent-...
1
vote
1answer
875 views

dport is not working on iptables command

In terminal I type : iptables -A INPUT --dport 443 -j DROP And it tells me : iptables v1.4.21: unknown option "--dport" what is wrong with --dport?
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1answer
839 views

ufw rules don't block deluge

I'm trying to keep deluged on my headless Ubuntu Server 14.04.1 from functioning when the server isn't connected to a VPN (I know many threads exist discussing the best way to accomplish that; I'm not ...
0
votes
1answer
263 views

linux gateway / firewall IPtables config

The KVM host is acting as a gateway / firewall for all of the virtual machine's it runs. It has a /26 public IP space configured on LAN interface em1: 1.1.1.1/26 It has a /30 rfc1918 IP configured on ...
0
votes
1answer
172 views

FTP and browser network connection issues in 14.10 Utopic

I have a remotely hosted website. For long I could FTP into it and upload web content, but now when I try, Nautilus tells me after a long waiting time that "oops, something went wrong". Normally I ...
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0answers
225 views

How to config PORT KNOCKING on CSF ubuntu server and access it by linux?

I'm trying to run port knocking work on a CSF on a small VPS, i setup this: 1 - the result of csf first test ok 2 - TCP_IN = "53,80" TCP_OUT = "53,80,113,443" UDP_IN = "53" UDP_OUT = "53,113,123" ...
1
vote
1answer
2k views

apache2 on ubuntu 14 - localhost works but ip doesn't

I've just installed apache2 on my box, along with php5. I can navigate to "localhost" and it works. But I can't access this webserver from another machine... or even locally using the IP address. ...
1
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0answers
660 views

Why is ip forwarding not working in xubuntu 14?

I upgraded my gateway computer from xubuntu 12 to 14 and the computers on my home network lost their internet connection. I found that the upgrade had uninstalled my old firewall, Firestarter, and ...
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votes
1answer
434 views

Firewall and virus software for Ubuntu 14.10 [duplicate]

I've only used a window operating systems in my life. I just began using Ubuntu 14.10 about a week ago after my old Windows OS was corrupted. Using Ubuntu 14.10, how does change the firewall settings?...
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
1answer
54 views

iptables and expressing your IP address to the rules dynamically

I've been recently spending my time refining my iptable rules to be a little more robust than Ark linuxs Simple stateful firewall to include defense against some other known and nefarious attacks. One ...
3
votes
1answer
14k views

UFW is blocking all even when I set rules to allow

I am using an ubuntu server, Now I am trying to enable the firewall using these commands: ufw default deny incoming ufw default allow outgoing ufw allow ssh ufw allow www ufw allow https ufw enable ...
0
votes
1answer
252 views

Iptables troubles

I used webwin for iptables management and reset the firewall over webmin (to clear out all the old stuff). I also disabled the feature Activate at book. After that I installed iptables-persistent for ...
1
vote
1answer
5k views

telnet: Unable to connect to remote host: Network is unreachable

I am not able to connect to gmail with telnet using any of the ports. I am using this command: telnet smtp.gmail.com 25 and it gives following error: Trying 74.125.68.108... Trying 74.125.68....
2
votes
1answer
4k views

using ufw to block outgoing traffic to website

I want to block traffic to a specific domain e.g. mysite.com. I tried blocking the ip address of the site but it does not work: ufw deny from 0.0.0.0 to ip_address_of_site I am still able to acess ...
1
vote
1answer
400 views

How do I set up a firewall/iptables using rc.firewall?

I am new to Ubuntu and am having a bit of trouble getting my firewall set up for my Network Security class. We are set up with 3 virtual machines - a Gateway, a Server, and a Client. We are supposed ...
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 ...
3
votes
1answer
1k views

ufw not blocking traffic

I have an apache2.4 webserver, and I am trying to block a malicious subnet using ufw. Here is the UFW setup: $ sudo ufw status verbose Status: active Logging: on (low) Default: deny (incoming), ...
1
vote
1answer
2k views

Whitelist IPs for ufw

I have set some rules in ufw to rate limit connections, as such: -A ufw-user-input -p tcp --dport 25 -m state --state NEW -m recent --set -A ufw-user-input -p tcp --dport 25 -m state --state NEW -m ...
2
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0answers
177 views

How do I find which OS layer (iptables, rp_filter, etc) is dropping a packet?

Let's say that I'm running a ping towards a machine and I see from tcpdump that the icmp echo reply is being received at the ethernet port but the ping program is not getting it. So I know that ...
0
votes
1answer
581 views

network bridge not forwarding traffic from span port on router

I want to run several security network tools in LXC containers like ntopng, suricata, snort, etc. I hooked one of my server's NIC's up to a port that is spanned to my firewall... so basically this ...
0
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1answer
57 views

I have some questions about Firewall [closed]

So I am pretty new to Linux (With the exception of Android), and being use to the old ways of Windows pretty much all I had to do for Firewall was turn it on and forget about it. However with Ubuntu ...
0
votes
1answer
373 views

Processes in docker cannot connect with ufw enabled

I'm trying to setup a server to use ufw with docker (via dokku.) When ufw is enabled, I cannot open connections from one container to another. When it's disabled, I can connect fine. As an example, I ...
1
vote
1answer
234 views

How can I tease Sonicwall?

In my college, I can't use the web, because they use Sonicwall network firewalls How can I tease it? For I use all websites in my college? Please see the result when I access a website blocked ...
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vote
0answers
144 views

Can't Connect to Apache2 Server From External Device (in LAN) Nor From External IP?

I forwarded ports 80 and 443 for my apache 2 server. However, if I: try connecting to the server via external IP or try connecting to the server from a local device via my local ip, I cannot gain ...
0
votes
1answer
786 views

Setting up an Ubuntu Server 14.04 Firewall. Can it Protect multiple pc's on a local network?

I am new to Ubuntu firewalls. I would like to setup an Ubuntu Firewall on computer #1 it can be connected wirelessly or by Ethernet. I have another ubuntu server running on computer #2 and windows 7 ...
0
votes
2answers
466 views

How to block parts of a website

I already use the hosts file to get rid of entire domains that are time sinks, but some websites that largely are wastes of time (eg reddit) have useful parts. So I'd like to allow www.reddit.com/r/...
0
votes
1answer
3k views

what could be blocking port 5060 on my ubuntu 14.04?

I have a ubuntu 14.10, and am trying to telnet into it via port 5060 but I keep failing. I always get the message "Connection closed by foreign host". I checked my iptable, it is default policy to ...
0
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1answer
315 views

Skype has stopped working on Ubuntu Studio 14.04.1

This is what Skype displays when I try to connect. I've tried reinstalling, but still no fix. When I sign in on my mobile phone it works, so I know it's an issue affecting only the desktop version.
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votes
3answers
4k views

The program 'iptables' is currently not installed

I am a newbie, so my apologies up front. I am trying to get DansGuardian installed (which I believe I have) and working. To get it working I need to filter IP traffic through the app via iptables. ...
2
votes
1answer
6k views

Refused connection of ssh

I installed openssh on my new Ubuntu14.04 server, turned on ssh, and enjoyed it after I finished installation. Every thing was fine; however, after just one night, I was blocked when using putty as ...
14
votes
6answers
5k views

Does spyware exist for ubuntu?

Someone I know said he had put spyware on my computer. Is he talking crap? I've been using Ubuntu 12.04 for nearly 3 years now and I've never seen any type of spyware, remote keyloggers or RATS (...
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2answers
1k views

find mac address of all connected systems [duplicate]

How can I find out how many system are connected to the local network and how can I get all IP and mac address of these systems. Is their any command/package to show the IP details? Can I use this ...
1
vote
0answers
178 views

how to block all tcp and udp and other protocol and only allow layer 2 communication?

sudo ufw disable sudo ufw default deny sudo ufw allow XXXX sudo ufw enable Does sudo ufw disable block layer 2 by default? How to block all TCP, UDP and other protocols, so only layer 2 ...
0
votes
1answer
296 views

Differences between UFW and GUFW

From what I have been able to piece together, the firewall that comes with Ubuntu is iptables, which is very complicated, so an easier way to access the firewall is through UFW and GUFW. UFW is ...
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0answers
563 views

Why aren't these ufw rules working?

I'm trying to configure ufw to only allow connections to 3 ip addresses on my local network, and deny everything else. Here's the commands I'm using: yes | sudo ufw reset sudo ufw default deny sudo ...
7
votes
2answers
7k views

How do you view all of the banned IP's for Ubuntu 12.04 via the command line?

I can't seem to find a quick command to just view all the banned IP's on the server. Or is there a file I can just edit? I'm guessing fail2ban is the one that inputs all the IP's to ban. Where do I ...
1
vote
1answer
1k views

What are the IP addresses in my iptables chain FORWARD settings in a Dokku/docker setup?

I've been playing around with Dokku on DigitalOcean (following this guide) and I'm trying to understand current firewall settings. So here's my setup: Ubuntu 14.04 Dokku Docker (as part of Dokku) ...
0
votes
1answer
137 views

keep getting added to hosts.deny + iptables

I am confused to why this has started to happen. On my local network, if I click 10-20 apache/http links my server will decide to add me hosts.deny file and block me on iptables. Its not just apache,...
0
votes
1answer
2k views

How to open the ports on firewall in Ubuntu? [duplicate]

I'm pretty new to Ubuntu. I just want to open the most common ports namely FTP (port 20 TCP/UDP) HTTP (port 80 TCP/UDP) SMTP (port 25 TCP) ETC I've tried all the ways in iptables, ufw, and gufw. ...
1
vote
0answers
149 views

Ubuntu Randomly Rejecting Hosts

currently I am facing a very strange problem: my Ubuntu is randomly resetting connections and I have no clue why. /etc/hosts.deny is empty (resp. just the default file with comments only, that comes ...
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0answers
69 views

Connecting to Ubuntu host not possible

I have an Ubuntu-Host which is connected via wlan (and for testing to wired net) to a local net. This Ubuntu-Host is not reachable via network by any other clients on the same network. But: If I do a ...
3
votes
4answers
3k views

14.04 missing “/etc/init.d/ufw”? my firewall never auto starts

I need to know how to fix the missing "/etc/init.d/ufw" file, is it some package or some command? I used the gufw to enable it, but on reboot my firewall was still off... I created a symlink /etc/...
0
votes
1answer
928 views

Ubuntu 14.04 denying incoming access

I just install a Counter-Strike: Source Dedicated Server on my Ubuntu 14.04 Desktop amd64 and I'm having trouble to allow incoming access to this server from the internet. I did a port forwarding on ...
4
votes
1answer
3k views

Iptables rules no longer honored

I installed Ubuntu Server 64-bit 14.04 a week ago. It worked fine for one to several days, then out of the blue, iptables became meaningless (I noticed FTP and such are down ). Only ports 22, 25 & ...
8
votes
2answers
10k views

What is MASQUERADE in the context of iptables?

In Iptables many times I see the target MASQUERADE. What is that. I searched and find lots of things. But I need some one explain me what MASQUERADE is in a so easy way? **If you bring an example ...
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vote
0answers
513 views

ufw is not working properly

I'm trying to enable ufw in remote ubuntu server. This server has two LXC container running. One container has nginx server running and I have hosted web application, right now every thing is working ...