Questions tagged [firewall]
A Firewall is an application or hardware device used to inspect and filter network traffic.
4,190
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Setting up Internet connection failover on Synolgy NAS
I currently have the following situation:
I have a Home LAN I use also as Small Office, just for myself
I have two WAN connections (both xDSL)
I have a Synology NAS (DS422+, if it matters) that is ...
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NAT pre/output/post routing/forwarding fails a few minutes after a reboot. What would ask the firewall to stop forwarding?
This morning (May 5, 2023), I found that my LAN stopped working on my Ubuntu 18.04 installation. All computers are locked out because the main server FORWARD rules are being ignored.
When I first ...
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SSL certificate for subdomain, which is routed to public IP masked on firewall, which navigates to local server
I have a web application hosted on local server. Which we have opened for public use by masking this local IP to public IP provided by ISP. So now website is accessible with public IP.
We required to ...
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Creating a firewall rule to deny access from an IP range to the internet
I hope I'm at the right place with my question. Already tried it in the Zyxel forum but they're not as active as you guys are. So I'm here.
I want that devices inside a specific IP range can not ...
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Iptsbles site to site vpn
I have installed strongswan site-to-site vpn,thats working fine. On server I have configured iptables with this commans iptables -t nat -A POSTROUTING -s 10.9.141.0/24 -d 10.10.27.0/24 -j MASQUERADE.
...
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Google Cloud Engine - Network unreachable (with NAT)
Context & issue
We would like to do maintenance on one of our Compute Engine instance (update dependencies via apt update/upgrade), but said instance does not have access to the public internet, ...
google-cloud-platform
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How do I block access to Whatsapp application on my XRAY server?
I'm trying to block my XRAY server clients from accessing Whatsapp mobile application . I blocked a list of domains :
wa.me
whatsapp-plus.info
whatsapp-plus.me
whatsapp-plus.net
whatsapp.cc
whatsapp....
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firewall blocking local network access even though firewall shows inactive
So I have 2 VPS, both Ubuntu.
it's as follows:
Has OpenVPN on it, and I use that VPN
Has a website that I would like to be able to connect to, but it's not connecting when my VPN is running from ...
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Debian 11 firewalld+nftables rules not taking effect
Update: after commenting out the line in /etc/hosts that is kinda like
#127.0.1.1 my-host.domain.edu my-host
and rebooting, the firewall does open the expected ports. I thought to do this because, ...
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Disable or Remove Local Firewall Policies
We recently had a few VM's provisioned but I didn't realize firewall settings were baked into the local policies, see below. These are Windows 2019 instances. A lot of the rules set are for services ...
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Disable Windows Defender Firewall pop up for a target folder
I'm encountering an issue with the Windows Defender Firewall every time I compile and run my Go program. It seems that the program's use of sockets is triggering the firewall each time a new version ...
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How does this data center setup work? Public gateway IP can route to unique subnet of public addresses?
we haven't been able to figure this out whatsoever, and this data center has no real support that explain how this is working. This is an unfamiliar setup to us but they assure us it's standard for ...
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Configuring ufw for Access via https, understanding the rules
I have a docker ecosystem running. Multiple containers need to communicate with each other. For reasons of my own I do not use the docker-supplied inter-container-communication but ordinary http/https ...
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ufw firewall not working as expected (block specific incoming IPs)
So, I see these Apache access.log entries coming in every minute:
mydomain.com:80 95.211.199.153 - - [19/Apr/2023:23:34:28 +0000] "GET /index.html HTTP/1.1" 200 1425 "-" "Leaf/...
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How to create two different firewall rules with the same name that applies to different profiles using PowerShell?
I have a server that has the following firewall rules.
I'd like to mimic this on a another server running the same OS. Currently, I have this rule.
How do I split it into two rules: one that is ...
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How to correctly pass firewall rules to the google-terraform-network module?
I want to create a network using the google-terraform-network module. Additionally, I want to pass the firewall rules I made as a parameter to the module so that the created network contains these two ...
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nftables: Possible to block SYN packets with payload?
Is it possible to drop all TCP SYN packets with a payload using nftables?
The man pages mention various length options, but none that I could get to work for TCP packets without syntax errors.
I am ...
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Limiting outbound traffic to AWS Management Console or other Amazon consoles
I've a network whose outbound traffic is strictly limited to a whitelist of sites or domains. I searched and couldn't find any documentation about how could I allow stations on this network to use AWS ...
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How can I check if an outgoing connection is blocked by local firewall?
I have a situation, where my server can't connect to an SMTP server, while my PC can. But the same server can connect to another SMTP server. I think that my firewall might be blocking it. How can I ...
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Gitea instance is being brute-forcely attacked
My Gitea instance is being brute-forced just as I write this text:
gitea | Invalid user yinsen from 94.23.30.184 port 55154
gitea | Connection closed by invalid user yinsen 94.23.30.184 port 55154 [...
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Drop ALL the TCP connections (ESTABLISHED,RELATED) in Ubuntu
I'm facing a few hosts sending a flood of requests to my webserver (NGINX). I'm trying to block them via iptables, with ipset and a good old DROP rule.
The rule is effective against NEW connections, ...
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I can't add any rule to iptables / iptables not saving
I want to forward tcp and udp traffic from wireguard ip address (10.66.66.2) to 0.0.0.0, but iptables doesn't want to cooperate.
OS is Oracle Linux 8, I use yum as package manager. Firewall.d is ...
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iptables: DROP on an interface does nothing, but works if I don't specify an interface
Setup:
Ubuntu 20.04 on a box with 5 physical ethernet ports (let's call them eth1 - eth5).
I have joined them all to a bridge ("br0") with brctl and they can all ping each other.
What I'm ...
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136
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Strongswan VPN with Checkpoint stuck on connecting
I am new to strongswan and linux so i'm trying to setup a vpn connection between a linux firewall cluster and a checkpoint gateway.
So this is my node list and resources:
root@Deb-FW-C1:/etc# crm ...
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37
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Do firewalld rich-rules apply irrespective of the allowed services in a zone?
Context: I have firewalld running on an AWS EC2.
Goal: I want to add a rich rule to the default zone (public) that allows traffic from a certain CIDR range/IP address range/subnet over port 443 (HTTPS)...
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answers
107
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Can not start etcd cluster when setting up a HA K8S cluster
I am following this article to set up a HA k8s cluster:
Guide: Kubernetes Multi-Master HA Cluster with kubeadm
I have three master nodes(3,4,5) and four worker nodes(2,6,7,8) (one of the worker nodes ...
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iptables per-user split tunnel leaking udp packets
I followed the guide here:
https://gist.github.com/GAS85/4e40ece16ffa748e7138b9aa4c37ca52
I've added a couple more rules for local traffic, but my setup is still leaking udp packets, on ports not ...
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VMWare ESXi Web Client access dies after some time
After applying IP filters on VMWare esxi's firewall settings for Web Access / Web Client rules, the allowed IPs work fine for some time like 5 hours.
Only the IP addresses I allow can access the ...
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Cannot 'sudo apt install <something>' after IPtables configuration
I'm trying to install some of the packages on Debian VM which is connected to another Debian machine (router). On the router default policy for FORWARD chain is DROP. I added rules for http(80), https(...
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answers
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How to apply DROP rule immediately (iptables/conntrack)
An external IP is connecting to my mailserver VM every second and I just want to block this IP immediately without dropping existing connections.
So I apply a DROP rule.
I even reloaded all the ...
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Block requests to "Visual Search" in Edge and "Search images with Google" in Chrome for internal web application
We have a web application that is used internally that displays highly confidential images.
Microsoft Edge has started displaying a button on the images that launches Visual Search, and Chrome has a ...
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I block ports using firewall still they are accessed
I am using Avast firewall. I blocked ports from 1024 to 55535 yet I see apps established connection on ports in that range.
As you can see on the screenshot, the machine is making mirror connection.
...
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198
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iptables rules not working for allowing a specific IP
I have a host with 2 network interfaces: wifi and site-site vpn (zerotier).
root@host:~# ifconfig wlp0s20f3
wlp0s20f3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1....
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1
answer
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Cisco ASA to Watchguard
I have never worked with watchguard firebox firewalls in depth before and we are replacing a Cisco ASA 5515 with a Watchguard M390. I am having a hard time interpreting the configuration settings in ...
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Stop exe from accessing internet - firewall blocks but DNS request is being made
We purchased this software a few years ago, we use it locally only. After some update this software received the function to save user files on their cloud. For security purposes we would like to keep ...
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477
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How exactly is docker circumventing my nftables?
My aim is to block all ports from non "lo" interfaces except for 22, 80, 443.
I don't want external devices to my Rasberry pi to be able to access anything else except for 22, 80, 443.
I ...
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Filtering traffic by MAC - nftables
TL:DR : I am building a network tap with a raspberry-pi that must remains stealth. I have a bridge (br0) between the switch interface (eth0) and the workstation (eth1).
Here is how i am building it (...
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iptables rules for dsvpn
on github i'm looking at this vpn project called dsvpn. it sets up some firewall rules by running iptables commands. One of them is (i hope the names are self-explanatory) :
iptables -t raw -I ...
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After setting a forwarding (routing) I cannot download files from servers
I have found these codes on www to create a proxy for a software:
sysctl net.ipv4.ip_forward=1
sysctl -w net.ipv4.ip_forward=1
iptables -t nat -A POSTROUTING -j MASQUERADE
iptables -t nat -A ...
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troubleshooting dns resolution, packet dropping, and dig/nslookup
I've been trying to troubleshoot an issue where using a curl lookup command takes a long time (sometimes) and is quick some other time.
TL;DR
Question: how do i troubleshoot further.
Connecting ...
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ConfigServer firewall enable SSH for dynamic dns
I am running ConfigServer Firewall on my server. Currently I have a few dynamic dns entries added to the LFD Dynamic DNS section. Those dyn dns hosts though cannot SSH to the server - I can only get ...
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2 VLANS on 1 Physical OpnSense Ethernet Port (connected to wifi access point) and 1 Captive Portals on each VLAN
I want to create a captive portal with different restriction per user account/role (student and teacher).
The Teacher can have unrestricted access.
The Student have restricted access. (only defined/...
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2
answers
84
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fail2ban - one IP banned multiple times by multiple jails - errors in log durin unbanning
I make few similar jails for different ports...
jail names: http_https_deny, dns_deny, ftp_deny, smtp_pop3_deny, ssh_deny
here firewalld and fail2ban settings for http_https_deny(other almost same, ...
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97
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Firewall blocking Port
I am running multiple Webservices on my Ubuntu 22.04 Server and want them to bind to specific Ports which works without problem but when trying to connect it is not working and portchecker returned me ...
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157
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Firewalld apply port redirection from rootless Podman containers to host
Is there a way to redirect ports for traffic that originates from the host or a Podman container and is destined for the host or another Podman container using Firewalld?
My use case: I am hosting a ...
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Which is the appropriate service to allow an ip range to access API Gateway + Cloud Storage on Google Cloud?
I'm trying to identify the appropriate service to allow only a certain IP range to make requests to API Gateway and Cloud storage. This is because we only want to accept request coming from cloudflare....
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154
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Apache2 http server and Openvpn server on the same machine
Installed Apache2 server on my Linux Mint 20.3 Cinnamon and I could easily reach my http pages from web pointing to the static ip address of my router where I have configured the right http port.
I ...
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366
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I am unable to access services on the WAN IP from within the network
Normally, this would not be a desired configuration, but I am setting up a NextCloud server, and to validate the domain, it requires that it be able to access it through the public IP address. No ...
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58
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Why does Windows 10 disconnects WIFI frequently, when Firewall is very restrictive?
On my Win 10, I've blocked all incoming/outgoing connections except: DHCP, DNS, LAN, Edge and couple other apps. After reboot Win 10 sees WiFi connection as connected/no internet => disconnects it ...
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How to create access point or virtual access point in Fedora server 37 to access localhost too
Hi I am trying to create an access point in ideal case virtual access point in Fedora server 37.
I can create a simple AP for wifi to LAN(wlp7s0 -> enp1s0 in my case) using these commands and I can ...
