A Firewall is an application or hardware device used to inspect and filter network traffic.

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3answers
306 views

Is there already a recommended IPv6 Firewall setup?

I'd like to switch from private-IPv4-subnet-behind-NAT to IPv6, but of course I have no intention of exposing my users' workstations "unprotected" to the net. Some obvious points up-front: Allow ...
5
votes
9answers
3k views

Block users from Social networking websites while firewall is down

We currently have a SonicWall firewall, which does a pretty good job a blocking Social networking websites like Facebook and Bebo. The problem we are having is that sometimes we need to temporarily ...
4
votes
3answers
2k views

Comparison of Firewall, Intrusion Prevention, Detection and Antivirus Technologies in Organizational Network Architecture

in these days i'm reading about intrusion prevention/detection systems.When reading i really confused in some points. First, the firewall and antivirus technologies are known terms for years, however ...
4
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2answers
8k views

Should I use TCP or UDP to run a web server

I have just installed Apache web server on my computer. I have managed to use it locally (I can open index.php from my computer using my web browser). But I would like to make my web site available ...
3
votes
1answer
476 views

Need help understanding capturing from Wireshark?

I am having issues with my FTP servers. Connecting, sending and receiving fail sometimes, and it is not consistent. I manage to capture and filter by IP the packets, I just need pointers on what can ...
3
votes
3answers
9k views

Enabling http access on port 80 for centos 6.3 from console

Have a centos 6.3 box running on Parallels and I'm trying to open port 80 to be accesible from outside tried the gui solution from this post and it works, but I need to get it done from a script. ...
3
votes
3answers
14k views

What does “incoming” and “outgoing” traffic mean?

I've seen many resources explaining how to set up a server's firewall to allow incoming and outgoing traffic on HTTP standard ports (80 and 443), but I can't figure out why I would need either of ...
3
votes
4answers
908 views

Is it alright to turn off firewall in a LAN using Group Policy?

Is it a good idea or common practice to completely turn off windows firewall in an AD domain using Group Policy? At this time, even the servers' firewall are turned off. The only device not affected ...
3
votes
2answers
418 views

Is my linux firewall secure?

I am newbie to linux firewalls and trying to setup my systems firewall for a public facing computer. Here are my requirements: Ports 80 and 22 should be open for HTTP requests and SSH logins Since ...
3
votes
5answers
3k views

Apache DDoS Protection in router (pFsense) [duplicate]

I'm soon going to change my infrastructure when I buy a new server. I'm going to replace my D-Link DIR-655 router with an pFsense router (and probably use the 655 as an AP) using my old server ...
3
votes
2answers
6k views

Why can't I ssh or ping my brand new Amazon EC2 instance?

I just created a free EC2 instance with all the defaults. It says it's running in the AWS Management Console. On the "Instance Actions" menu, I click "Connect". I copy the DNS name provided (looks ...
3
votes
7answers
4k views

4 NICs or 4-port NIC?

I want to setup a firewall handling two ISP connections and two routers. For that I am planning to use an old Pentium 3 machine. Now, should I use four network interface cards or a 4-port NIC? Do ...
3
votes
7answers
859 views

Is Windows 2003 Firewall appropriate for a web server?

I currently have a colocated server being protected by a hardware firewall, however this firewall is old and I want to replace it. I was wondering if the built-in Firewall software for Windows 2003 ...
3
votes
1answer
773 views

Will you allow NetBIOS into your DMZ?

Is it secure for a firewall to allow NetBIOS connections from the internal network to the DMZ? If not secure, what are the risks? If secure, what is the FUD about and what are the counterarguments? ...
2
votes
2answers
157 views

How to have ntpd serve only my local subnet

I have a few servers with public Internet IP addresses like A.B.C.x. One of my hosts (A.B.C.10) runs ntpd and I have it syncing it's time from europe.pool.ntp.org. Now I only want to allow hosts ...
2
votes
2answers
737 views

Virtualizing Firewalls/UTM

So Sophos UTM (Astaro Gateway UTM) can be virtualized in Hyper-V, VMWare, vSphere etc. Now I'm new to virtualization, so am wondering how the networking would be configured in this situation. ...
2
votes
1answer
264 views

Examples where an AWS Security Group is not sufficient as a firewall?

Currently I am using only an AWS security group for one of my EC2 instances but have given some thought to adding a firewall to that stack as well. I'd be looking at using either iptables, or ...
2
votes
2answers
3k views

Ports used for Lync Edge server

I have Lync 2010 Standard deployed in my environment, along with an edge server. On my firewall I have NAT'd the public address(s) to the server. Right now I have all the ports opened for these ...
2
votes
1answer
683 views

iptables: block traffic by IP range for specific website

there is a web-hosting server with several sites on it. I need to block some subnets (IP ranges) for some website(s). Is it possible at all? I've tried something like this: iptables -A OUTPUT -m ...
2
votes
1answer
4k views

User Friendly port knocker (port knocking client) for Windows?

It seems "It's me" is the most popular port knocking client for windows… Except… it sucks. It works for console-savvy users such as me, but, unsurprisingly, all my users (3 people) hate console ...
2
votes
1answer
3k views

HOw to check firewall rules in Centos

I have centos 5. I tried iptables -L and it gives the following output Chain INPUT (policy ACCEPT) target prot opt source destination RH-Firewall-1-INPUT all -- anywhere ...
2
votes
2answers
434 views

How long does a blocked connection from Iptables last? Is there a way to set the timeout?

iptables -A INPUT -m state --state NEW -m recent --set # If we receive more than 10 connections in 10 seconds block our friend. iptables -A INPUT -m state --state NEW -m recent ...
2
votes
2answers
193 views

Just LB or also Web Servers in Demilitarized Zone?

In a load balanced environment, is it necessary to have all of the web servers in the DMZ? Or will just having the Load Balancer in the DMZ achieve the desired security? If it matters, the web ...
2
votes
2answers
4k views

Disable firewall, ubuntu 9.04

How can I disable firewall on ubuntu, or how can I check which ports are listening, and how can I add some new ports to be listened to? Thank you
2
votes
2answers
1k views

Smoothwall NOT giving out DHCP

I have a Smoothwall machine with 'green + red' setup. The Smoothwall machine can see the outside world and I can connect to it from inside my network with its local address (I can also connect from ...
2
votes
2answers
8k views

Windows Firewall 2008 Server - Allow only given IP in, block all others

I've got a Windows 2008 Server. It has the built-in windows firewall on it. I've played around with the Advanced settings where I can setup inbound/outbound rules, but it doesn't appear that I can ...
2
votes
3answers
622 views

Mac OS X Firewall Configuration: what's the easiest way to do it?

On occasion I need to configure the firewall on OS X machines (10.5), and I've been trying to figure out the best (read: easy without sacrificing too much control) way to do it. So far it seems like ...
1
vote
1answer
485 views

Limit Connections Per IP Windows 2008 R2 x64

Hello I have been searching for a solution to this, what I want to accomplish is the ability for me to define firewall rules that will limit the amount of connections to certain ports from the same ...
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0answers
1k views

Mikrotik router RDP brute force blocking with whitelist

Masters, We have a miktorik router, and we would like to block RDP brute force, but we need whitelist also to allow our collegaues to connect without blocking them. (they sometimes hitting wrong ...
1
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0answers
108 views

Wireless Bridging two Sonicwall Firewalls

We have two sites (essentially two small buildings side by side but we are unable to run CAT5 cable between them) which are currently linked via a wireless bridge. We will be splitting the sites so ...
1
vote
3answers
371 views

Netflow/IPfix Analyzer for network threats and anomalies

I'm evaluating various options for Netflow/IPfix based analyzers which focus on identifying security threats and anomalies. It would be highly appreciated if someone can provide a list of tools with ...
1
vote
1answer
2k views

iptables rule order

I have noticed the following iptables rule order executed by a program: iptables -A INPUT -p all -j ACCEPT iptables -A INPUT -p all -s ip_address -j REJECT I thought that based on the ordering ...
1
vote
1answer
156 views

Directory Listing (ls) error ONLY in port 22 (SFTP)

Using SFTP I suddenly get this result: Status: Connecting to 64.207.146.82... Response: fzSftp started Command: open "root@64.207.146.82" 22 Command: Pass: ********* Status: Connected to ...
1
vote
1answer
1k views

Firewall predefined rule property cannot be modified

Using a stand alone Windows Server 2012 Standard edition (no Active Directory), I Tried to establish a simple remote desktop with a custom port number, but could not modify the port number in the ...
1
vote
1answer
1k 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 ...
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3answers
5k views

FTP Transfer Very Slow When Windows Firewall Enabled

We have a scheduled task that transfers a large file (~130 MB) between two Windows servers using the Windows command-line FTP program. It's painfully slow (taking about 30 minutes) and occasionally ...
1
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3answers
745 views

Linux : restricting outgoing on an application basis

I typed : netstat -atlpvn and noticed that applications like gedit and python had foreign addresses outside the network (the network being a single computer connected to the internet). Is there ...
1
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1answer
148 views

Recovering a server from being an open relay

One of our Mac Pro machines running Apache was inadvertently acting as a forward proxy with a public IP, after some organisation proxy rules changed. Consequently it was discovered by spammers and ...
1
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3answers
2k views

Unable to access internal network through PfSense WAN port

Our branch office is unable to connect to our internal network for some reason. However we can connect to the branch office domain controller from behind PfSense. The following is our setup: ...
1
vote
4answers
142 views

Do I need a hardware firewall for Win 2003?

We have had a Win 2003 server at a co-lo for a while. It is used as a web server and has a very cheap hardware firewall between it and the internet. Ports 3389 and 80 are the only ones forwarded to ...
1
vote
3answers
546 views

Windows Server 2008 firewall: do I need to set outbound rules?

In Windows 2008 I see inbound and outbound rules, I can open TCP and UDP in both directions. So if I open some port in TCP and some in UDP inbound and the connection works, why do I need outbound ...
1
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2answers
2k views

iptables command to clear all existing rules

My server is Red Hat Enterprise Linux Server release 5. What is the correct/proper command to clear all existing iptables rules defined in /etc/sysconfig/iptables (so that I can start defining/adding ...
1
vote
1answer
2k views

with ec2, are all internal instances able to connect to each other, or does the security group apply?

Just a little confused, normally a firewall applies to everything externally, and all internal servers (instances) can connect freely with each other. With AWS, it comes with a firewall/security ...
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3answers
978 views

Best Firewall product for hosting/housing environment?

I am searching for a firewall product (appliance or software) for an hosting/housing environment. The biggest problem is that the rules get very complex as more customers are behind the firewall. Some ...
1
vote
1answer
215 views

Is there a robust, low-hassle solution for “port-knocking” based protection of SSH ports?

By robust and low-hassle I mean NOT involving complex iptables setups, NOT involving apache, NOT requiring an additional client program, NOT requiring fragile shell scripts running from cron, etc. ...
1
vote
3answers
1k views

tunnel over https proxy server (client-server model)

I need to get reliable Internet connection behind a restrictive firewall. facts: firewall handless HTTP CONNECT to anywhere as long as it goes to destination port 443 I have some servers publicly ...
0
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1answer
35 views

How to list EC2 security group *rules* from within instance?

I have SSH root access to an EC2 instance but no access to the AWS Console / AWS KEY & SECRET. My incoming traffic to this host on all TCP ports except 22 TCP seems to be blocked - I cannot ...
0
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0answers
132 views

Enabling the Internet Connection on an EC2 Windows Server 2012 Machine

I've disabled the firewall: netsh firewall set opmode disable I've made sure to accept all inbound and all outbound connections: Is there anything that I should be installing or adding on to the ...
0
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0answers
46 views

windows firewall , some ports not listening

I've added an inbound connection rule for my windows 8 firewall on windows server 2012: I've restarted the Windows Firewall. When I check that port using this program, it says that it is not ...
0
votes
1answer
157 views

How do I block all access to machine except port 3389 using Open vSwitch

I can allow access to the machine and block everything else using: ovs-ofctl add-flow xenbr0 "dl_src={mac-address} priority=39000 dl_type=0x0800 nw_dst={ip-address} idle_timeout=65000 action=normal" ...