1
vote
2answers
425 views

force LAN hosts to go through proxy

I have an IPTables firewall on a Debian server, with a bunch of hosts behind it with masquerading. In the upstream network I don't have direct access to the internet, and I need to go through a proxy ...
0
votes
1answer
202 views

Why is UFW blocking some allowed internal connections?

My set up is this: Server 1 (192.168.1.1) - nginx (load balance) - Ubuntu 12.04 LTS Server 2 - uwsgi - Debian 7.1 Server 3 - uwsgi - Debian 7.1 UFW on server 2 and server 3, is blocking ...
0
votes
2answers
60 views

How to open all ports for specific length of time?

I'd like to open all ports for specific user for specific length of time using IPtable. The current rule i have is: $IPTABLES -A FORWARD -i $LAN_IF -o $OUTSIDE_IF -p tcp -s 192.168.10.34 -m state ...
-1
votes
1answer
94 views

is there a way to prevent mac spoofing using debian [duplicate]

I have a debian server that acts as a router for a network, and I am planning on making it so I am able to block network access for certain computers, what do you think would be the best way to do it? ...
0
votes
1answer
47 views

IP Tables though Simple Router Machine

I have being setting myself up a router, for mainly for dns+dhcp functionality (mess about with alot of virtual machines). I have two interfaces eth0 and eth1. Eth0 can be see as the WAN with eth1 for ...
0
votes
1answer
114 views

split traffic on two eth ports

I have a linux Proxmox server with two ethernet ports. The problem is that I have two uplinks that I would like to use with different bandwidth limitations. The first uplink maxes out at 100mbs and ...
1
vote
2answers
801 views

How to log the ip addresses trying to connect to a port?

Is it possible to log all ip addresses that trying to connect or connected to port "5901" in linux debian? how can i do that? Regards
0
votes
1answer
187 views

Can't login to Debian (OpenVZ guest) server after setting up IPTables. How to Fix it?

I have an OpenVZ VPS server with Debian. I just setup IPTables to allow the SSH port rebooted it. (Also set the rules to auto load on startup). Now I can't login to the server! How to fix this? Note ...
3
votes
1answer
1k views

ufw blocking apt and dns

I installed ufw on my Debian system like the following: # aptitude install ufw # ufw limit 22 # ufw allow 80 # ufw allow 443 # ufw enable # ufw status verbose Status: active Logging: on (low) ...
1
vote
1answer
127 views

Restrict VPN Clients to VPN Server

I've setup a VPN server using Debians pptpd. This all works, but I want to restrict incoming connections so they can only access ports on the VPN server and not get access to other machines on the VPN ...
4
votes
2answers
2k views

Secure NAT setup with iptables

I have a Debian running device that needs to act as an internet-gateway. On top of that I want to provide a firewall that not only blocks inbound traffic, but also outbound traffic. And I figured ...
1
vote
1answer
703 views

Config Server Firewall: Spamming my email | lfd on localhost: Suspicious process running under user www-data

I have just installed and configured CSF and I am getting 100s of spam emails containing this message. lfd on localhost: Suspicious process running under user www-data Time: Wed May 23 01:05:52 ...
0
votes
1answer
384 views

Pros vs Cons of Rate Limiting ICMP [duplicate]

I am configuring Config Server Firewall and here is the default config for ICMP. I have read on the internet that disabling or limiting ICMP can cause huge headaches on your server. However I have ...
0
votes
1answer
4k views

Config Server Firewall: You need to install the missing perl modules and then install cxs

I am trying to install config server firewall however when i follow the tutorial and run install.sh i get the following error. Can anyone help? root@localhost:~/csf# sh install.sh Configuring for OS ...
1
vote
3answers
3k views

Why is iptables command throwing errors?

I typed the following on my Debian system: iptables --list And got the following: libkmod: ERROR ../libkmod/libkmod-index.c:816 index_mm_open: magic check fail: b007fa57 instead of b007f457 ...
-1
votes
1answer
154 views

Firewall blocks outgoing email

On my Debian server running a Django website, I have an error when I need to send an email. The error received is Exception Type: gaierror Exception Value: [Errno -2] Name or service ...
0
votes
1answer
1k views

Debian 6. What would be a good UFW initial firewall configuration?

I opened ports 22 25 80 443 993 995 The output of ufw status is... Status: active To Action From -- ------ ---- 22 ALLOW Anywhere 25 ALLOW ...
2
votes
1answer
191 views

Firewall recommendation for Debian 6

What would you recommend to a firewall newbie for a firewall solution that can be handled remotely, maybe either by ssh or the browser?
0
votes
2answers
625 views

NFS support in iptables (or other firewall)

How do I enable NFS mounts/shares with iptables with DROP policy? NFS uses dynamically assigned ports, thus it is difficult to use with firewalls. I have an NFS server and a few clients. I would ...
1
vote
3answers
269 views

Modify Debian firewall rules programmatically

I'm currently deploying on Rackspace Cloud Servers with Debian installs. I have an application that uses a remote coordinator which communicates with all of my servers in order to start various ...
0
votes
2answers
246 views

iptables misconfiguration is blocking outgoing connections

Here are the rules I setup.. iptables -P INPUT DROP iptables -A INPUT -i eth0 -p tcp --dport 80 -j ACCEPT iptables -A INPUT -i eth0 -p tcp --dport 443 -j ACCEPT When I try to make an outgoing ...
2
votes
1answer
169 views

Is a firewall really necessary? [duplicate]

Possible Duplicates: Why should I firewall servers? Why would I need a firewall if my server is well configured? For a single web server that only listens on 22/80/443, is a firewall ...
3
votes
3answers
496 views

What is Runlevel 'S' on Debian/Ubuntu for

According to Wikipedia, 'S' is supposed to be a standard runlevel: "Single-User Mode". But if I'm not mistaken, the Single-User mode on Debian is Runlevel 1. One Debian article I found claims, that ...
1
vote
1answer
42 views

Is this a valid IPtables command?

I have to add redirect rules for several thousand IP ranges but I am complete newbie when it comes to IP tables and want to make sure I got this right.. iptables -t nat -A PREROUTING -p tcp -m ...
0
votes
1answer
195 views

Firestarter on debian server. Should I activate SSH?

I have just installed Firestarter on my Debian server, because I want an easy-to-use tool to administer the firewall on this server. The plan is to restrict access to some ports (e.g. 8080) and I've ...
1
vote
1answer
138 views

fail2ban on Ubuntu (defaults okay?)

I run an Ubuntu-based web-server (LAMP) and have installed fail2ban. Does it have sensible defaults to restrict malicious activity via SSH and any LAMP ports out-of-the-box? Or, does it need to be ...
1
vote
1answer
970 views

Postfix connect timing out remotely, working fine locally

Running Postfix on Debian I cannot connect to send mail any more. It worked until approximately a week ago. I do not recall touching the configuration of the server during that time, which makes it ...
0
votes
1answer
2k views

error: “net.netfilter.nf_conntrack_acct” is an unknown key

i have the next error when i run 'sysctl -p' error: "net.netfilter.nf_conntrack_acct" is an unknown key net.netfilter.nf_conntrack_acct = 1 net.ipv4.netfilter.ip_conntrack_max = 9527600 ...
2
votes
3answers
2k views

Can I Use iptables rate limiting to temporarily block FTP server brute-force attempts?

This is along a similar line to other posts on brute-force attacks, but a bit more specific: We are able to enforce decent passwords, generally, and user name policy also avoids falling prey to what ...
1
vote
3answers
560 views

Debian Blocked IP's

I am debugging access to a remote service via. my Debian VPS. IPTables is used and allows outward port 21 traffic. The remote service is an FTP server (which I can access from my own PC and is not ...
0
votes
2answers
778 views

Force all outbound HTTP connections through a proxy

We run a few society websites behind a University firewall that mandates that all traffic goes through an internal squid cache / proxy. While export http_proxy= works perfectly in the shell I'm ...
0
votes
5answers
8k views

how to open port 53 for bind

how to open port 53 for bind on debian server? [xxx.xxx.xxx.xxx] 53 (domain) : Connection refused
3
votes
7answers
2k views

Good linux firewall?

I am looking for a good firewall for debian 5 which is a web server. Are there any good options apart from iptables? Thanks
4
votes
5answers
7k views

iptables port forwarding on debian

I'm trying to setup a simple port forwarding firewall and I can't make the basic non-firewall configuration to work. I have setup the iptables script as follows #!/bin/sh # interfaces LAN="eth1" ...
56
votes
13answers
25k views

What steps do you take to secure a Debian server?

I am installing a Debian server which is connected directly to the Internet. Obviously I want to make it as secure as possible. I would like you guys/gals to add your ideas to secure it and what ...