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

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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. ...
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3answers
11k 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 ...
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4answers
787 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 ...
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2answers
404 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 ...
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5answers
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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 ...
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2answers
5k 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 ...
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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 ...
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7answers
856 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 ...
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1answer
749 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? ...
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2answers
661 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. ...
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2answers
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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 ...
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3answers
3k views

Ubuntu only allow incoming access from 192.168.0.0/8 or server IP address

How can I make it that only approved IP addresses have access to my Ubuntu server 12.04 I only just set it up.
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1answer
656 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 ...
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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 ...
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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 ...
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2answers
399 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 ...
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2answers
192 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 ...
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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
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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 ...
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2answers
7k 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 ...
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3answers
619 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 ...
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0answers
999 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 ...
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1answer
134 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 ...
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1answer
903 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 ...
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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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2answers
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UFW/IPTables: after setting default outgoing deny, and port 80 outgoing allow, curl still doesn't work

With UFW, I disabled all outgoing and ingoing traffic by default. However, I do allow port 80 in and out: sudo ufw default deny incoming (deny all incoming) sudo ufw default deny outgoing (deny all ...
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3answers
4k 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 ...
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3answers
672 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 ...
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1answer
144 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 ...
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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: ...
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4answers
140 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 ...
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3answers
518 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 ...
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2answers
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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 ...
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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
908 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 ...
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1answer
211 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. ...
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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 ...
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53 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 ...
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15 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 ...
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1answer
118 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" ...
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2answers
646 views

Cisco ASA/PIX Can't Access Internal Resources Behind NAT [duplicate]

My servers are natted 1:1 as follows, i.i.i.i maps to x.x.x.x where i is an internal IP, and x is the external IP. From an i.i.i.i machine, I cannot access x.x.x.x resources... What special ...
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1answer
186 views

How to route the traffic from a specific port through a socks 5 server?

I'm running oracle sql on port 1521. However I can connect on it from a remote server only through a socks5 proxy(due firewall restriction). The client that I use to connect to the sql server doesn't ...
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1answer
542 views

NAT / Port Forwarding with iptables firewall [duplicate]

I've got the following setup: firewall (iptables) eth0 internal interface, 192.168.2.10 ppp0 external interface, public_ip (IP masquerading) server1 (192.168.2.11), service 1 (port 443) server2 ...
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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 ...
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1answer
133 views

DNS through Cisco VPN

We have a Cisco ASA providing a VPN gateway for users. Currently when users VPN'n from outside the network they can access file servers from their IP addresses but the shares do not response via share ...
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1answer
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IP Table, what does this construct mean ::INPUT ACCEPT [0:0]

I am looking at an IP Table construct, what does the following mean : :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] thanks
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1answer
134 views

iptables: How to create a rule for a single website that does not apply to other websites?

Virtual Dedicated Server hosts 10 websites. 1 firewall made with iptables If one of those 10 websites gets hit by too many ping requests coming from one IP address, how do I limit or drop it without ...
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1answer
85 views

File uploads taking more time

We recently moved to a new server. We have observed that the file upload done from the ftp command is taking around 5sec for 5MB file. But same file uploaded through CURL command is taking about 140 ...
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0answers
352 views

Fowarding port in iptables to internal server

I'm running cPanel/WHM with ConfigServer Firewall (csf). I want to forward port 8080 on my webserver to an internal server with an IP of lets say 10.1.1.1 thats running a webserver on port 80. How ...
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1answer
661 views

Firewall on a KVM host, prevent access to VM:s

I have a Linux machine running KVM with several VM:s, all have public IP:s. For the time being I have everything routed through a bridge (br0) and this works well. I also need a firewall on the host ...