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Questions tagged [firewall]

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

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What are the named ports for iptables?

When setting up iptables you can name the port ssh which will use port 22. Is there a list of all the named ports? Specifically I need ssh, http, https and mysql.
Jason Christa
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Good low power server/pc for firewall?

Does anyone know of a low power server/pc that have 2 NIC's, so it can be used for a (OpenBSD) firewall? Sandra
Sandra
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Ufw and Iptables. Which is better and why?

I am a newbie to this domain, so i kept researching on ufw and iptables. But I cant distinguish them clearly because in every article /blog both of these names are present and I am really confused whether these are similar or not. I know ufw is a…
HelloWorld
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AWS EC2 deny single ip address and allow all

I have a AWS EC2 instance and want deny access on port 80 for a single ip address (a bad bot). AWS console it seem support only "allow" rules. How deny a single ip address?
ar099968
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tcp flags in iptables: What's the difference between RST SYN and RST and SYN RST ? When to use ALL?

I'm working on a firewall for a virtual dedicated server and one of the things I'm looking into is port scanners. TCP flags are used for protection. I have 2 questions. The rule: -p tcp --tcp-flags SYN,ACK,FIN,RST SYN -j DROP First argument…
Kris
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How to create a Windows 2008 Advanced Firewall rules group definition through the command prompt

Is there a way to create a group, or add to an existing group, to a rule in Windows Advanced Firewall (preferable through a command prompt or WSH script). Edit:
frogstarr78
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Why buy high end hardware firewalls?

There exist firewalls from Juniper and Cisco that cost more than a house. So I wonder: what does one get from a $10.000+ firewall compared to an 2U server with 4x 10Gbit network cards running e.g. OpenBSD/FreeBSD/Linux? The hardware firewalls…
Sandra
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Do I need seperate iptables rule for ipv6 address?

On my debian 5.0 server, I setup some iptables rules like below: ACCEPT tcp -- eee.fff.ggg.hhh aaa.bbb.ccc.ddd tcp dpt:80 DROP tcp -- 0.0.0.0/0 aaa.bbb.ccc.ddd tcp dpt:80 aaa.bbb.ccc.ddd is my server's ip…
Long Cheng
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How to block mysterious remote requests?

My CentOS server is experiencing huge (millions a day) requests looking like this: Srv PID Acc M CPU SS Req Conn Child Slot Client Protocol VHost Request 62-1 - 0/0/335 . 0.00 1947 204049 0.0 0.00 0.85 …
Nils Munch
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Is there a way to see what is actually filtering TCP port communication?

nmap -p 7000-7020 10.1.1.1 Will output all the filtered ports Starting Nmap 6.40 ( http://nmap.org ) at 2015-03-04 12:18 EET Nmap scan report for 10.1.1.1 Host is up (0.00091s latency). PORT STATE SERVICE 7000/tcp filtered…
Eduard Florinescu
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automatically block IP address after many failed login attempts

I am receiving a lot of failed login attempts (1 per sec) on a Windows 2008 server, I have already set local security policy to automatically lock an account after too many login attempts, but is there a way to automatically include an IP adress in…
Allie
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Managing parallel rules for ipv4 and ipv6 iptables?

We've recently started experimenting with IPv6, and one of the first issues we're having to contend with is dealing with a completely separate set of firewall (Linux iptables/ip6ables) rules for the two protocol stacks. Our firewall logic is based…
larsks
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Reviewing firewall rules

I need to review firewall rules of a CheckPoint firewall for a customer (with 200+ rules). I have used FWDoc in the past to extract the rules and convert them to other formats but there was some errors with exclusions. I then analyze them manually…
chmeee
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Windows Firewall has port 80 open but prevents Apache from making connections

I have a Windows 7 machine serving a very few (but important!) pages. I have an exception that allows any traffic to port 80*, but Apache 2.2 still can't serve pages (though I can see them from the machine itself). If I disable the Windows…
Charles
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Is there a secure way to allow IIS 7 in a DMZ to access a DB server behind the firewall?

Our network admins are adamant that it is insecure for our web servers, which are hosted in the DMZ, to access the DB server behind our firewall. To get round the problem, we access the data via web services or WCF. I feel that this is an…
Al Polden
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