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

learn more… | top users | synonyms

1
vote
0answers
2k views

Ubuntu 12.04 LTS - vsftpd problem. No connection. Connection refused

i have a problem with vsftpd server running on Ubuntu 12.04 LTS. Here is the configuration: ubuntu Server address - 192.168.5.100 router address - 192.168.5.1 roger/# grep -v "#" /etc/vsftpd.conf ...
0
votes
0answers
67 views

Beginner Help Configuring Iptables

I have just started to configure iptables and I am wondering what basic rules you would recommend that I use for the things that I need. Here is what I am doing: I want my default policies for ...
0
votes
0answers
159 views

I have UFW block messages from local network machines, how can I analyse if they are malicious?

I'm getting a lot of messages in my UFW log, and I'm trying to figure out if these are malicious or just normal. A UDP broadcast is coming from a windows laptop x.x.x.191, and some from our synology ...
2
votes
0answers
128 views

found someone lurking in my LAN, not sure what to do next

I have DD WRT router with internal numbers all falling within 192.168.1.0/24. I was looking on my firewall records this morning and found someone at 10.10.109.100 got blocked from accessing port 5353 ...
0
votes
0answers
41 views

How is IP getting autobanned by Ubuntu?

I have an ubuntu server running postfix/dovecot and shorewall firewall. Every so often I see in the logs that external IP address are getting banned but I can not figure out where or how this is ...
0
votes
0answers
228 views

Configure Firewall to use SSH Tunnel Through Port 80

I am having some issues configuring iptables to use SSH Tunneling through port 80. Here are my iptables rules. :INPUT DROP :FORWARD DROP :OUTPUT DROP -A INPUT -m state --state RELATED,ESTABLISHED -j ...
1
vote
0answers
148 views

ubuntu server apf-firewall configuration

I have not used the apf-firewall before and I'm having trouble configuring it. I have already try setting the iptables but it fails to start, so what more do I need to do? thank you
0
votes
0answers
68 views

Help Configuring Iptables Rules

So I am accessing my server remotely using PuTTy. I am using port 80 for SSH because port 22 is blocked at my school. I successfully configured Iptables to accept port 80 and I dropped all other ...
4
votes
1answer
1k views

Ban IP by country in UFW

I want to block a country in my server, but I don't know which rule I must use in UFW (or iptables). For example, people from US and other countries can see the site, but visitors from Russia can't. ...
0
votes
1answer
490 views

UFW, allow from wlan to eth

I would like to use my ubuntu 12.04 notebook as a wifi hotsport to my smatphone. Everything is going ok, using dnsmasq and hostapd and allowing ports 68 and 53 on UFW. But to access the web the UFW ...
0
votes
0answers
586 views

Bypass proxy in Ubuntu

In my hostel there is Cyberoam firewall. Therefor I am unable to access Facebook. I searched also and tried using jellyshell but it takes too much time. Is there any option using tor or vpn? Tor ...
0
votes
1answer
514 views

What's the difference between -p tcp and -m tcp in iptables?

I just noticed an entry in /etc/sysconfig/iptables along the lines of -A INPUT -p tcp -m tcp --dport 138 -j DROP I am not so sure why there has to be two switches here for matching protocol TCP, ...
2
votes
1answer
6k views

How can I allow ssh connection from an IP subnet on port 10022 using iptables?

I need to set up a server with public IP for bandwidth testing, and I already have a script to drop all incoming traffic except for the ports I need. I have changed the ssh port from default (22) to ...
1
vote
2answers
990 views

Ubuntu - apt-get not working behind restricted internet access

I have Ubuntu 12.04 64-bit boxes running in a company but they have internet browsing and firewalls for security. When I do apt-get update or install it fails. But I have a remote server which ip is ...
0
votes
1answer
91 views

No matter what I researched and did I can't connect to my MySQL server

Ubuntu installed MySQL for me through LAMP. When I connect with SSH I can login with the root user but not the user i created myself. When I use HeidiSQL I can't login with anything. I ran these ...
1
vote
1answer
328 views

Understanding Iptables

iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 7000:7010 -j ACCEPT I trying to understand the -m state --state NEW part. Searching through the man pages and correct me if I am wrong ...
1
vote
0answers
60 views

Can a weak Ubuntu user password be a risk for ONLINE security?

Can anyone gain an unauthorized remote access to my Ubuntu machine? Does having a strong user password really helps prevent this? Or firewall just doesn't let anyone in by default, regardless of the ...
6
votes
6answers
1k views

Do I need a firewall for my desktop?

I don't have a router, but I mostly use my desktop for online shopping and torrenting. So, do I have to enable the firewall? I hope not, because I'm really dumb and I don't think I will be able to ...
0
votes
1answer
564 views

Ubuntu Firewall: Apache only visible on lan

How can I add a rule to the Ubuntu firewall that makes Apache server only accessible from the internal LAN? ufw status ng@ng-laptop-kv:~$ sudo ufw status Estado: activo Hasta ...
1
vote
1answer
170 views

having problem with squidGuard. Need help [duplicate]

when i write down this command on my terminal for configuring squidguard squidGuard -d this error shows up squidGuard: error while loading shared libraries: libdb-4.6.so: cannot open shared object ...
0
votes
1answer
120 views

Issues with shorewall

I'm new to using Ubuntu OS and its interface and using terminal. Recently I was trying to deploy squid, and shorewall firewall. Even though shorewall is running I can't get through one command, i.e. ...
0
votes
1answer
118 views

iptables forwarding rule

I entered the following rule into my iptables: sudo iptables -t nat -A PREROUTING -p tcp --destination-port 80 -j REDIRECT --to-ports 1337 and then when I went to remove it, I couldn't find it ...
0
votes
1answer
966 views

Connecting to NAT virtualbox guest from bridged network

I've setup a Virtualbox Ubuntu 12.04 server using Vagrant. I can ssh to it and even ping my desktop from it. What doesn't work is to ping the guest OS from my desktop. I've tried to flush the ...
1
vote
1answer
301 views

UPNP - How to configure GUFW

I have a TP-LINK TD-W8968 router with a mediaserver (UPNP/DLNA) port. The port has a USB stick with media content. I can access this content via XBMC and Totem/Movie player without any hassle. But ...
2
votes
2answers
2k views

How to block all but one or two websites without browser extensions? [duplicate]

I want to block all, but one or two websites. This question is therefore relatively close to, but different from the following Parental controls with different settings for different users ...
3
votes
1answer
118 views

UFW python documentation

I'm trying to access ufw with python, but on line 53 of backend.py, they raise a weird error that makes no sense: Traceback (most recent call last): File "mymodule.py", line 1467, in ...
0
votes
1answer
2k 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 ...
2
votes
1answer
3k views

Apache (and other services) work on localhost, but not IP address

My Apache server is working correctly on port 80. When I try to enable SSL on port 443, I can connect via localhost (telnet localhost 443) but not via IP address (telnet xxx.xxx.xxx.xxx 443). To ...
4
votes
1answer
660 views

Why ufw is blocking my outgoing traffic?

Here is my status: $ sudo ufw status verbose Status: active Logging: on (medium) Default: deny (incoming), allow (outgoing) New profiles: skip To Action From -- ...
1
vote
1answer
760 views

How to configure a firewall that only allows a few webpages and dropbox and U1 services?

Can anyone give a step-by-step how-to that explains how to block all outgoing internet traffic to all websites, but allows only a selected list (needed for working, fi. online dictionaries) allows ...
0
votes
1answer
256 views

Screen Sharing Behind Firewall

I've setup my brother's computer with Ubuntu. I would like to be able to control his screen with his permission, to configure and instruct him when needed. However, he is on a provide IP provided by ...
1
vote
1answer
90 views

How does ufw handle conflicting rules?

I recently had the following conflicting rules on ufw 445/tcp ALLOW 192.168.1.0/24 445 DENY anywhere 445 DENY anywhere IPV6 ...
0
votes
0answers
111 views

Help with ssh between machines on local network [duplicate]

I have two machines on my local network (both with Ubuntu 10.04) and I want to ssh (and rsync) between them. The two machines have fixed IPs 192.168.0.15 and ...17 Both computers frequently ssh ...
1
vote
0answers
874 views

SSH connections rejected after UFW allow 22

I am trying to setup UFW on a 12.04 server. SSH works great with UFW off. Setting root@ugvps:~# ufw enable Firewall is active and enabled on system startup root@ugvps:~# ufw status Status: active ...
2
votes
0answers
164 views

How do we allow a certain mac address in a FORWARD chain through iptables?

I set the iptables rules in default. # IPTABLES IN DEFAULT iptables -P INPUT ACCEPT iptables -P OUTPUT ACCEPT iptables -P FORWARD DROP How will allow a certain mac address in a forward chain? I ...
2
votes
0answers
880 views

IPTABLES > MAC Filtering

I am newbie. I tried DHCP Mac filtering is not enough to secure our networks and I think iptables will... This is my concept: I set a new laboratory (LAB) network. My other network is connected to a ...
1
vote
1answer
129 views

How do you install and configure TuxGuardian in Ubuntu 12.04?

Can anyone guide me on the process to install TuxGuardian in Ubuntu 12.04? Its a freeware application available at: http://tuxguardian.sourceforge.net
1
vote
0answers
381 views

UFW Firewall Rules, has a hole in it. Please help

Can someone please look at the below output for me. I have my UFW on deny/deny, and here are the rules. But if I leave my Ubuntu Server on, with a Windows XP VM, and let Instant Messenger run in the ...
1
vote
1answer
117 views

iptables help needed in 1304

I've setup my raring-ringtail machine and decided to use iptables after removing ufw to have more control over my network security. However, I'm stuck at one point. First, I've set default policy to ...
0
votes
1answer
3k views

Postfix is timed out while sending

I have just set up postfix (with tasksel install mail-server) with the default settings. Unfortunately, I can not send e-mails from by SMTP server. Here is my main.cf: # See ...
1
vote
0answers
250 views

New Server - apache will not serve outside LAN

New server, running well 12.04 LTS on HP ML350. Apache = great, inside our LAN. Apache = timeout, from WAN (NAT forwarded from firewall). I have cleared all Iptables, read & checked every ...
4
votes
1answer
408 views

Could someone tell me whether my OS is communicating with the internet?

I edited iptables so that when the VPN service is disconnected, no program will access the internet. Well, I did an experiment. I disconnected the VPN service manually and immediately did a ping by ...
0
votes
1answer
343 views

Change UDP port with iptables for VPN clients

What I want to do is say that for all UDP connections on interface ppp0 that have a destination port of 53, change that destination port to 1053. I am attempting to change the destination port of UDP ...
2
votes
2answers
1k views

Cannot open port

I've been struggling to open the port 5432 for remote PostgreSQL access. Which I installed on a Ubuntu 10.04 desktop machine. Here is the shell log: xybrek@ubuntu:~$ sudo ufw allow 5432 [sudo] ...
1
vote
0answers
71 views

Can not permanently clear iptable rules

I use the following commands to flush all iptable rules: sudo iptables -F sudo iptables -X sudo iptables -t nat -F sudo iptables -t nat -X sudo iptables -t mangle -F sudo iptables -t mangle -X sudo ...
3
votes
2answers
2k views

Why is ufw logging 'BLOCK' messages regarding a port for which ufw is configured to 'ALLOW' connections?

Here's an example log message: May 25 10:36:07 myserver kernel: [7057243.392334] [UFW BLOCK] IN=eth0 OUT= MAC=00:02:55:67:82:eb:00:06:b1:3a:ef:62:08:00 SRC=69.197.128.26 DST=192.168.100.101 LEN=44 ...
2
votes
0answers
172 views

How should I configure Ubuntu firewall?

Just discovered Gufw, and I'd like to set it up. But I haven't found any documentation telling me what I should/should not allow. I'd like to be able to use it but the only documentation on the web ...
0
votes
2answers
21k views

SSH connection refused when connecting remotly

I set up my Ubuntu server and it can connect to itself when running ssh localhost. However, when I run Putty on windows 8 I get a "connection refused" error. I have, to the best of my ability: ...
1
vote
2answers
1k views

ufw firewall operation

I have always run the program UFW as my firewall in Ubuntu, and been satisifed with its performance. When I installed Ubuntu 13.04, and enabled ufw, I was not able to access the internet, and all ...
2
votes
1answer
244 views

Open ports for development purposes

I'm doing some Java ME Development in my brand-new Ubuntu laptop, coming from a now replaced Windows Vista one. What I'm trying to do is run a Mobile Simulator that acts as an HTTP Server -receives ...