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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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Will tcpdump see packets that are being dropped by iptables?

I have a firewall with these simple rules: iptables -A INPUT -p tcp -s 127.0.0.1/32 --dport 6000 -j ACCEPT iptables -A INPUT -p tcp -s 192.168.16.20/32 --dport 6000 -j ACCEPT iptables -A INPUT -p tcp --dport 6000 -j REJECT Now, suppose I am using…
Pablo Santa Cruz
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Hardware Firewall Vs. Software Firewall (IP Tables, RHEL)

My hosting company says IPTables is useless and doesn't provide any protection. Is this a lie? TL;DR I have two, co-located servers. Yesterday my DC company contacted me to tell me that because I'm using a software firewall my server is "Vulnerable…
user80776
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4 answers

How to make Firefox trust system CA certificates?

Our network admin recently enabled HTTPS inspection on our firewall/router. For IE users this is fine because the certs have all been distributed via Active Directory for domain-joined machines. However, we have a number of Firefox users that are…
Wes Sayeed
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What firewall ports do I need to open when using FTPS?

I need to access an FTPS server (vsftpd) on a vendor's site. The vendor has a firewall in front of the ftps server. I have a firewall in front of my FTPS client. I understand that ports 990, 991 and maybe 989 need to be opened up for control…
user3293
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4 answers

Copy UFW rules between servers

I'm doing a hardware refresh on a my Colo, I just need to copy my UFW rules from my old server to my new server. I dont seem to be able to get them copy all the active rules from my old server to my new one. How do I copy my active UFW rules…
Squidly
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Fail2ban jail.local vs jail.conf

Does jail.local file act as an override to jail.conf or as a replacement to jail.conf? When I was learning about Fail2Ban from tutorials, most of them usually say either to copy jail.conf to jail.local and make the edits there and some of them says…
Neel
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Which ports for IPSEC/LT2P?

I have a firewall/router (not doing NAT). I've googled and seen conflicting answers. It seems UDP 500 is the common one. But the others are confusing. 1701, 4500. And some say I need to also allow gre 50, or 47, or 50 & 51. Ok, which ports are…
hookenz
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Rate limiting with UFW: setting limits

UFW's man page mentions that it can setup iptables rate limiting for me: ufw supports connection rate limiting, which is useful for protecting against brute-force login attacks. ufw will deny connections if an IP address has…
Tom
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Will everyone having Globally Accessible IP's in IPv6 be kind of a security nightmare?

Possible Duplicate: Switch to IPv6 and get rid of NAT? Are you kidding? I'm thinking about the way that in IPv4 most of the time you have a single point to configure a firewall on, mainly your router, but if everybody has a Globally Accessible IP…
leeand00
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iptables show just one chain

tldr: How can I get iptables to show just one chain? I can have iptables show just one table, but a table consists of multiple chains. I need to find where in chain INPUT is the last rule (usually but not always the REJECT all rule). I've tried awk…
bgStack15
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Block employee access to public cloud

First of all, let me state that this is not my idea and I don't want to discuss whether such an action is reasonable. However, for a company, is there a way to prevent employees to access public cloud services? In particular, they should not be able…
marsze
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UFW comment existing rule?

I'm trying to comment an existing ufw firewall rule, but I can't find the exact command I can easily add a rule with comment like: sudo ufw allow in on eth0 to any port 80 comment 'test' But how do I comment an existing rule?
Emax
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Windows Advanced Firewall: What does "Edge Traversal" mean?

this should be a really simple one: In Advanced Windows Firewall on Windows Server 2008+, Properties > Advanced, what does "Edge Traversal" mean? I Googled it, of course, and was unable to come up with a concrete answer, and I was especially…
Django Reinhardt
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How can I find out if a port is opened or not?

I have installed Apache server on my Windows 7 computer. I was able to display the default index.php by typing http://localhost/ in the address line of my browser. However, I am still unable to see this page by typing IP address of my computer…
Roman
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How to remove access to a port using firewall on Centos7?

Had a port opened up to for public use using firewall-cmd, I wanted to limit this port to a specific IP which I found the answer for on this SITE. I used the following to open it: $ firewall-cmd --permanent --zone=public --add-port=10050/tcp $…
mcv
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