53
votes
Accepted
How to tell which windows firewall rule is blocking traffic
(Note: this method has been working at least on Windows 7, 10 Pro, Server 2012 R2)
Following steps will lead you to the rule blocking your connection:
Open a Windows console (with Administration ...
- 746
34
votes
Accepted
How to detect if a network is blocking outgoing ports?
tl;dr
Run this command to test a specific port (fast).
time nmap -p 22 portquiz.net
Run this command to test popular ports (slow).
time nmap portquiz.net
Run this command to test all ports (...
- 1,096
30
votes
Accepted
Using Windows Firewall to block a specific IP on Windows 10
Open Windows Firewall with Advanced Security by running wf.msc. On the left, select Inbound Rules, then under the Action menu, choose New Rule.
On the Rule Type page, choose Custom.
On Program, ...
- 39.3k
26
votes
Is it possible to create firewall that only allows legitimate webserver traffic on port 443 and not any other service?
Yes, and they don't need any magic here, just trivial matching on the TCP packet contents. Even though SSH and TLS (SSL) encrypt their payloads, the protocol headers themselves are still ...
- 400k
23
votes
Accepted
Cannot ping a Windows 11 machine
After poking around I managed to enable ICMP responses on my Windows 11 machine:
Open Windows Defender Firewall and select Advanced Settings in the sidebar. Switch to Inbound Rules via the Getting ...
- 466
22
votes
How to block everything (all incoming and outgoing internet access) except those applications are in firewall white-list?
You do not need any 3rd party firewall software.
By default windows firewall functions as follows:
Inbound - Block all unless in the list (Whitelist)
Outbound - Allow all unless in the list (...
- 331
21
votes
How to config Windows firewall so VM Host-only can ping Windows 7
I ran into this issue recently when I started doing Linux development on a Windows laptop where the source code was on the host and it was shared over CIFS* to compile on a CentOS VM.
Open Windows ...
- 521
19
votes
Accepted
How to open a firewall port in Windows using Power Shell
You can refer to the guide here.
The command to open port 80 is:
netsh advfirewall firewall add rule name="Open Port 80" dir=in action=allow protocol=TCP localport=80
You need to specify:
name ...
- 3,983
18
votes
Is it possible to put UFW on CentOS?
Since ufw is available in the EPEL repository, it can be directly installed as a package:
yum install -y epel-release
yum install -y ufw
- 181
17
votes
Am I paranoid, or are corporate firewalls censoring entire countries?
I've seen a variety of vendors doing content filtering based on country of origin. China and Russia are usually the ones with filtering turned on by default, or at least have some kind of alerting ...
- 2,080
17
votes
Accepted
What are the IP ranges to block the entire Russian Federation?
7,255 IP address blocks assigned to the Russian Federation
As of June 2018, there are over 7,200 IPv4 address blocks assigned to the Russian Federation. The largest of them, with 524,288 addresses ...
- 1,754
16
votes
Accepted
What does it mean if a public IP address looks like a private IP address?
There are several ranges of 'private' ip addresses, as defined in RFC1918. These are:
10.0.0.0 - 10.255.255.255 (10/8 prefix)
172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
192....
- 16.1k
15
votes
Accepted
How to block range of incoming IPs in Windows Advanced Firewall
First calculate the sub-network CIDR notation. In 13.54.0.0 to 13.54.255.255 IPv4 range, the first two octates are constant (the network prefix) and the remaining last two octates are variable (host ...
- 10.5k
15
votes
Accepted
PFSense Stuck At "Please wait while the update system initializes" while uninstaling or upgrading any package
Check your pfSense version. I had to update from pfSense 2.4.5_1 to pfSense 2.5.0. That solved the problem for me.
- 166
15
votes
PFSense Stuck At "Please wait while the update system initializes" while uninstaling or upgrading any package
I had to go to System / Update / Update Settings and set to previous stable version 2.4.5 deprecated bc I am still on 2.4.5-RELEASE-p1.
After doing that, package manger didn't show any updates for a ...
- 151
13
votes
Accepted
How do I stop my Mac from asking to accept incoming network connections?
This might be caused by a missing or wrong digital signature. Like Apple explains:
If you run an unsigned app that is not listed in the firewall list, a dialog appears with options to Allow or Deny ...
- 30.8k
13
votes
How to block everything (all incoming and outgoing internet access) except those applications are in firewall white-list?
In an elevated shell window, do
Set all profiles to block inbound/outbound traffic:
netsh advfirewall set allprofiles firewallpolicy blockinbound,blockoutbound
Remove all rules:
netsh advfirewall ...
- 261
13
votes
Accepted
Windows 10 defender firewall MpsSvc and Internet Sharing Services (ICS) consuming high CPU usage
I had the same issue on Windows 10, Firewall + ICS service constantly taking up 10% of CPU time.
I don't have Windows Defender enabled so couldn't follow the top answer's instructions. Instead:
...
- 4,425
12
votes
Is there a simple way to detect ISP port blocking?
This will take a lot of time but will get you the list of all blocked ports:
#!/bin/bash
COUNTER=1
while [ $COUNTER -lt 65535 ]; do
echo $COUNTER
curl portquiz.net:$COUNTER --...
- 223
12
votes
Accepted
Why does NTP require bi-directional firewall access to UDP port 123?
You only need allow incoming traffic NTP's ports if you are acting as a server, allowing clients to sync to you.
Otherwise, the existance of an NTP state will automatically determine whether the ...
- 196
12
votes
Windows 10 defender firewall MpsSvc and Internet Sharing Services (ICS) consuming high CPU usage
I was having the same issue but I do use Windows Defender's firewall. Resetting the firewall defaults worked for me.
I found the fix at https://answers.microsoft.com/en-us/windows/forum/windows_10-...
- 221
12
votes
Accepted
firewall-cmd - add-forward-port don't work
THE REAL PROBLEM:
The command...
firewall-cmd --permanent --zone=public --direct --add-rule ipv4 filter FORWARD 0 -d 0.0.0.0/0 -j ACCEPT
firewall-cmd --permanent --zone=public --add-forward-port=...
- 1,096
11
votes
What are Inbound and Outbound Rules for Windows Firewall?
Outbound means you initiate the connection and the traffic starts flowing outward of your computer to the destination you intended. Example you connect to a server.
Inbound means someone else from ...
- 221
10
votes
Accepted
How forward packets from network interface to another
You'll need some sort of masquerading statement. The reason behind this is that, currently, packets arriving from eth2 to eth1 are identified by 10.101.0.0/16 addresses. Those 10.101.0.0/16 packets ...
- 558
10
votes
Accepted
Why can ping.exe get the IP of a domain with no responding?
Why can I get the IP of the domain with no responding?
Because you don't actually get the IP address from the domain itself. You always get it from a separate database – the DNS (Domain Name System).
...
- 400k
9
votes
How to permanently disable firewall in Red Hat Linux
For version 7 of CentOS or RedHat Enterprise you must use the command systemctl.
For example:
#Check status:
systemctl status firewalld
#Stop firewall:
systemctl stop firewalld
#Disable firewall:...
9
votes
How to block docker-mapped ports with a firewall from outside the host without messing up docker routing inside the host?
It looks like I can bind my exposed container ports to localhost only.
docker run -d -p 127.0.0.1:9009:9009 someserver
- 261
9
votes
Accepted
Shares not accessible by other computers if Windows 10 firewall is ON
I manually added a rule to the firewall to open TCP port 445. This resolves the issue by allowing SMB2 and SMB3 over TCP. However, this solution is less than ideal since it does not answer the problem ...
- 311
9
votes
Accepted
Allow PowerShell remote access only from one address
Like explained in this article: Enabling PowerShell remoting for only a specified set of IP addresses.
(for each client pc1/pc2/pc...) you have to:
enable-psremoting
next: remove the winrm-listener ...
- 740
9
votes
Accepted
Windows 10 Firewall warns about being disabled on every login
You can disable Windows Defender Firewall with Group Policy. In the administrative templates for the computer, go to Network | Network Connections | Windows Defender Firewall | Standard Profile (or ...
- 39.3k
Only top scored, non community-wiki answers of a minimum length are eligible