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

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3
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1answer
706 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
513 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
2answers
2k 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
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1answer
594 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
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1answer
2k 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
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2answers
359 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
4answers
4k views

outbound ports that are always open

What are some ports that can NEVER be blocked outbound in firewalls, as doing so will stop basic internet use? Some I can think of are: port 53 udp/tcp -- dns, blocking this will prevent users ...
2
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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
2
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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 ...
2
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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 ...
2
votes
3answers
601 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 ...
2
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8answers
2k views

Open source firewall or commercial firewall

In what cases would it be considered OK to use open-source firewalls to protect/secure/filter a company network? There seems to be many open source firewall alternatives (pfSense, smoothwall, ...
1
vote
0answers
534 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
vote
3answers
295 views

Securing a guest VM to give it internet access, but block access to host LAN

I have a Linux guest VM running under a Windows host. If I set the networking mode to NAT, the guest can get internet access (which I want), but can also access the hosts LAN (which I dont). For ...
1
vote
1answer
100 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
702 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
822 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 ...
1
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3answers
577 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
136 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
1k 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
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4answers
138 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
491 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
1k 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
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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 ...
1
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3answers
821 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
206 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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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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4answers
108 views

iptables not installed on centos

If a machine does not have iptables installed, is there still a firewall running? If yes, how to I disable / change rules? if I enter the command iptables I receive the response: iptables v1.4.7: ...
0
votes
2answers
213 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 ...
0
votes
1answer
148 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 ...
0
votes
1answer
1k 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 ...
0
votes
1answer
118 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 ...
0
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3answers
2k 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.
0
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1answer
1k views

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
0
votes
1answer
128 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 ...
0
votes
1answer
907 views

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 ...
0
votes
1answer
82 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 ...
0
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0answers
282 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 ...
0
votes
1answer
566 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 ...
0
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2answers
1k views

How to block torrents using ADSL modem? [closed]

I'm looking for a solution for a small office.
0
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2answers
290 views

Can I hook a firewall inside a network and VPN connect to another network?

I'm wondering what I'd have to do to make the following scenario possible: _____________ __________________ | | | | | Network A | | Network ...
0
votes
1answer
10k views

Internet connection sharing windows server 2008 R2

I have one windows server 2008 r2, and that server has 4 network interfaces (3 private, 1 internet connection). I would like to share internet connection with other 3 networks. Windows server firewall ...
0
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2answers
432 views

Is it safe to ublock 587, SMTP submission port?

We have had problems before with SMTP port 25 (smtp) - some PC's were sending spam mail throught that port. So we blocked that and only allowed only outgoing smtp servers we needed. Howerver, i read ...
0
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3answers
3k views

MS SQL Server Firewall Ports

I've recently found myself in the position of quickly deploying a production app on SQL Server 2008 (EXPRESS), and I've been having some issues with configuring firewall rules between our web server ...
0
votes
1answer
946 views

Intermittent disconnect: which needs replacing, the router or the modem?

We have a WatchGuard SOHO 6 with the latest firmware (6.4.1) and an ISP-supplied DSL modem. The firebox's PPPoE settings look like this: We've been having a problem lately where our internet ...
0
votes
1answer
628 views

Multiple SSL services using single IP address or multiple DHCP on single interface

So, in the world of SSL/https you can just bind a new static public IP address to the firewall internet interface and use one SSL service (like an https://site, Outlook Anywhere or something like RDP ...
0
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2answers
4k views

Configuring keepalives with TOAD client communication

I have a scenario where long-idle sessions of TOADSoft client communication with the Oracle server seem to be torn down as they timeout on an intermediate state-full firewall. These sessions could ...
0
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2answers
552 views

Firewall on VPS - use windows built in, or 3rd party?

First time VPS user, and still a beginner at Windows Server 2003. Is the built in (simple) windows firewall considered sufficient if all I'm going to do is expose a few ports and block everything ...
-1
votes
1answer
108 views

impact of HTTP CONNECT on a mandatory web proxy policy

Consider a firewalled network with the high-level requirement that normal web browsing should work, but nothing else (e.g. ssh and Skype are forbidden). All traffic is blocked, except for outgoing ...
-2
votes
1answer
109 views

How is my firewall making all websites look like a login page [closed]

In the morning this question came across my mind. You would notice my poor knowledge on firewalls. My office installed a new firewall. I am provided a new username and a password. And here we have a ...