1
vote
1answer
82 views

configure exim for system email forwarding (outside) , on a server with dynamic ip, behind a DNS router

Trying to configure exim to deleaver email to the outside world. I/We need to send email outside just for centralize certain admin notifications. Working on an already configured debian webserver, ...
0
votes
1answer
278 views

Socket Connection Refused (raspbian) but ports are open for connections

I'd like to establish a connection between my client and raspbian. Within my network, I can connect to my service at any time without any problems. Now I want to connect to my service via the ...
2
votes
2answers
224 views

Do I need a special firewall on a personal computer

I am relatively new to Linux and was wondering about security issues. Most people agree that a virus-scanner is not useful on a linux system, but what about a firewall? I am using Debian wheezy stable ...
2
votes
1answer
246 views

ufw firewall rules for security.debian.org

What is a practical way to manage a whitelist of firewall outgoing connection rules for http://security.debian.org (on a server that blocks all outgoing connections by default)? My understanding is ...
4
votes
1answer
5k views

IPTables - Port to another ip & port (from the inside)

I currently have a NAS box running under port 80. To access the NAS from the outside, I mapped the port 8080 to port 80 on the NAS as follow: iptables -t nat -A PREROUTING -p tcp --dport 8080 -j DNAT ...
2
votes
1answer
295 views

How to interpret and react to Shorewall log?

I see the following pattern in every 2-3 sec, for several minutes in syslog: Shorewall:net2fw:DROP:IN=eth0 OUT= MAC=aa:bb:cc:dd:ee:ff:gg:hh:ii:jj:kk:ll:mm:nn SRC=12.34.56.78 DST=98.76.54.32 LEN=60 ...
2
votes
1answer
322 views

Make box only communicate on lan only?

I am running a VM with Debian as the guest OS (I can choose another distro). It has nginx running along with some other software. Some of the software tries to make outgoing connections (for example ...
0
votes
2answers
2k views

How to set up firewall on Debian Squeeze

I have set up Apache, MySQL, PHP, SSH (which I use to connect to the VPS), Node.js, MongoDB and ProFTPd. Now, I want to have a firewall on the system, so that no one hacks the system. For instance, ...
1
vote
1answer
492 views

How can I move firewall settings from one Debian Squeeze web server to another?

I configured a Debian Squeeze virtual machine in VMWare on my laptop. I configured it with a very restrictive set of firewall rules using Firestarter. I then uploaded a copy of its disk image to use ...
2
votes
2answers
442 views

Security with Kernel IP Forwarding Enabled

I recently enabled IP Forwarding on a production web server that also acts as a VPN server. What, if any, security issues did I just set myself up for? And are there any iptables rules I should set ...
0
votes
3answers
535 views

EBtales not working

I wanted to go a little bit further and install EBtables (the 2-layer filtering and routing table). The purpose of it was to only allow the minimal necessary(IPv4 and ARP). To test it I ran: ebtables ...
6
votes
4answers
6k views

Fail2ban block with IPtables doesn't work on Debian Lenny. [moved ssh port]

I've recently decided to do some security maintenance. I saw my logs, and there were some tries against my SSH server. At first, I moved away the SSH port from the default 22. After it, I read ...
6
votes
4answers
3k views

Debian: Which firewall for a newbie?

I have to install a firewall on my server (so without X Server). It's a debian lenny. If it is possible, I want to avoid the use of iptables. Is there a way to install/configure a firewall for a ...