Questions tagged [firewall]
a technological barrier designed to prevent unauthorized or unwanted communications between computer networks or hosts
1,242
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Setting up a reverse proxy on home lab
I'm very new to Linux and bash. I'm working on a homelab (machine a) project.
My ultimate goal is to set up Nginx on my server and connect externally (machine c) to Docker apps File Browser, possibly ...
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How to deal: external Jenkins port does not work
I have jenkins service working fine on internal and local levels (I can just open localhost:8080 or 192.168.x.x:8080 in the browser and it gives me Jenkins "sign in" page)
But I have ...
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I can't connect to Ubuntu server from local network, but can from outside
This is a weird one that has been driving me crazy for a while. I just can't work it out.
I'm running Ubuntu 22.04 (with all latest patches) on a Dell PowerEdge-r710 server. It's hosting a variety of ...
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Ubuntu Router configuration with UFW
Going down the ubuntu 20.04 server route and using UFW.
Steps so far (from a clean install)
Network Layout attached
networking configured with netplan - YAML file below - question here is do I need ...
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UFW block internet connection while using proxychains, How could I configure UFW?
I downloaded Tor, I edited proxychains.conf, uncommented dynamic_chain, proxy DNS - no leak for DNS data, proxy DNS. I added at the end of the proxychains.config file 5 different socks5 server IPs and ...
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156
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BIND9 on Ubuntu 20 - Cannot configure Zone to work properly
I installed it on Ubunto 20 and configured two zones
Options config file
acl internal {
localhost;
localnets;
192.168.70.0/24;
10.200.157.0/24;
};
options {
...
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170
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Restrict access to Docker container port to ip adresses
There are several docker containers on my server, exposing ports. Now I try to restrict the access to the ports to IP-Adresses being able to insert rules without allowing the policy. I apply IP-Tables ...
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SSH Connection Timed Out Ubuntu 20.04
I've looked through a million threads on this topic but nothing has worked. I'm trying to ssh into my linux through port 22. Connection is refused.
UFW is inactive and firewall-cmd is not downloaded
...
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Automatically created iptables rules created by Docker seem strange
Here are the rules that I don't understand (those are created automatically by docker on my ubuntu machine):
-A FORWARD -i docker0 ! -o docker0 -j ACCEPT
-A FORWARD -i docker0 -o docker0 -j ACCEPT
So ...
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External HTTPS succeed, internal HTTPS requests timeout on home server
I am running Ubuntu Server 22.04.3. I am using it to serve an API built on Flask, which goes through Gunicorn and NGINX to hit the outside world. The server works as expected for requests served over ...
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UFW allow all IP from ASN
How to allow access to ubuntu with UFW firewall for all addresses belonging to one ICT provider with its ASN number (Is it possible?)?
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cant enable UFW firewall
I am trying to set up a code-server on my ubuntu 22.04.
However I came to the realisation that my firewall wasnt enabled and tried enabling it using the instructions on this other thread : https://...
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Port Forwarding to another machine Rust gameserver
I need to forward UDP port 28015 of my local machine to another machine with port UDP 28021. Rust Game Server. (Redirect incoming traffic on a specific port to a different IP address with altern port)
...
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wireguard + ufw = unable to limit access to specific port
So I'm trying to limit access to port 5432 (postgres) by using ufw and unable to do so. The connection is allowed still
sudo ufw deny 5432/tcp
sudo ufw route deny in on wg0 from 10.0.10.2
root@vpn-...
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Connection via SSH works once or twice then never again for that client
I have recently set up a Ubuntu Server minimized. I initially used the server through an SSH with client1 but after one use I kept getting Connection Timed Out when attempting to ssh from client1. I ...
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Cannot access samba from outside LAN
I have samba server running on Ubuntu 22.04. I wish to access it from external machines. If a device is on the same local network I am able to open the smbd:// network address no problem (using the ...
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UFW blocking port forwarding
I am running Ubuntu Server as a home network router, which works fine otherwise. I also have another server on the network which hosts all of my content and services. So let's say, for example, I'm ...
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1
answer
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Is this a good firewall to keep brute force atackers out?
I am wondering, is the script below a good firewall script to keep brute force attackers out off my desktop?
iptables -F
iptables -A INPUT -i lo -p all -j ACCEPT
iptables -A OUTPUT -o lo -p all -j ...
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756
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curl to localhost fails in 20.04
I have host machine 20.04 and guest VM box 22.04
I am trying to run the curl command and on both machine getting the same error.
Host running this:
sudo ufw status
Status: active
To ...
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1
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Network card issues after reinstall of 20.04
PC with PCI Lan card and motherboard Lan had previously worked fine on 18.04 and 20.04, was upgraded to 22.04 but found application compatibility issues so reinstalled 20.04. Now the integral Lan is ...
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Diference between IPTABLES RAW PREROUTING and MANGLE PREROUTING
I'm looking for configs to prevent DDoS attacks and UPnP Flood, since I've started to create rules, every advice was to add rules to filter table, but it takes too much CPU process, so started to ...
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Why ports added to firewall are still closed?
I have added ports 25 and 80 to the firewall and enabled the firewall but even after reboot when I check the ports, they are still closed?
What else do I have to do?
Warmest regards
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Can't connect to remote MySQL (v. 8.0.33 | ubuntu 22.04.2)
On the server with the operating system ubuntu 22.04.2 installed MySQL version 8.0.33 with the following configuration:
/etc/mysql/mysql.conf.d/mysqld.cnf
#
# The MySQL database server configuration ...
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allow certbot validation and github action connection to digitalocean network firewall
I have this digitalocean droplet that I served as staging instance and has network firewall on it. As it is a staging instance I made it work like a private access only by adding our outline vpn ip on ...
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156
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Unable to remote access the web server running on Ubuntu machine
I'm unable to remote access nginx server or express server or any server running on Ubuntu in the same network
I tried every solution found on Google, chat gpt but no benefit
I'm able to ssh on Ubuntu ...
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Ubuntu - Tool for UDP rate-limit
I have a SIP gateway machine that I would like to apply some kind of rate limit on the host machine.
Something like - If an X number of connections happens under Y seconds -> Block source-IP and ...
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Uable to connect Ubuntu server by remoting
Hello I'm newbie of Ubuntu system. I have some problem that I've figured out for a while but I could not solve it yet. I could not remote to Ubuntu 22.04 server from my laptop (Putty said connection ...
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336
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Port forwarding not working
I have a machine on my home network I am trying to port forward (for rust if that helps) and I need to get these done
TCP: 27015, 27036, 28016, 28083
UDP: 27015, 27031-27036, 28015
I have allowed all ...
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Rsyslog not listening to UDP ports on Ubuntu 20.04
I have configured an Ubuntu 20.04 as my syslog server, to receive logs from Cisco Meraki. This should then send to Microsoft Sentinel SIEM.
My issue is that Rsyslog is not listening to UDP port 514 or ...
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SSL on internal network
I have a firewall (connected to the internet) with mod_proxy installed on apache. Behind the firewall I have several web-servers running. The issue here is SSL. I like to have everything on SSL, also ...
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Cannot Ping Server Despite UFW Inactive, Server Can Ping Other Devices
I'm running Ubuntu Server 22.04.2 LTS on a computer on my home network, connected via wifi. It can connect to the internet, and can ping other devices like my main Windows PC and my phone just fine, ...
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Login to another machine inside firewall
we are a small company working with laptops in a shared office setting. We are inside a shared firewall managed by the company renting out office space, and we can not configure this in any way.
For ...
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strange entries in ufw log
I have a very permissive firewall configuration, where I have almost all ports open:
$ sudo ufw status verbose
Status: active
Logging: on (low)
Default: allow (incoming), allow (outgoing), deny (...
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UFW allow rule with destination and port
Setting up UFW firewall on Ubuntu I wish to allow connections on port 22 from my local network only. I use next command:
ufw allow from 192.168.1.0/24 to any port 22
For me is unclear in the part &...
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IP addresses of ubuntu servers which apt-get connects
My server uses Ubuntu 22.04 LTS. I have a very restricted firewall (UFW), that is, I have run these commands:
sudo ufw default deny outgoing
sudo ufw default deny incoming
But, I would like my system ...
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UFW - Port is reachable for everyone although only certain IP's are opened
I run an Ubuntu 22.04 server on an VPS with a current version of UFW.
Further i run an docker instance with firefox - https://hub.docker.com/r/jlesage/firefox
The port is routed to 5800 to access this ...
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1
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what is 'target: default' of a zone's configuration in firewalld?
I am currently using ubuntu 20.04 machine and installed firewalld as the firewall manager service.
While looking at the configuration of 'public zone' , i can see as below,
public (active)
target: ...
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Mikrotik SSHD error: connect to host 9x.xxx.xxx.xxx port 7346: Operation timed out
I changed the router for my dedicated server from TP-Link to MikroTIK and upgraded router os to 7.8, the configuration on the host machine itself did not change, only the router was changed:
I opened ...
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2k
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How to set ufw to allow Remote Desktop Sharing on Ubuntu 22.04?
I know there is a command such sudo apt ufw allow <app> but the problem is I don't know what is the app name.
So if I enable ufw I can't connect to my ubuntu device from my mac via RDP, and I ...
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nmap on local host shows "filtered" on port which is stated as "open" on remote host
My question is similar to this but I'd like to fix and understand the error without having to rely on the possibility that factory-resetting my router will fix it for me. I also found this which is ...
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Cannot SSH into host on local network using TCP wrappers, despite allowing "sshd : LOCAL" in /etc/hosts.allow
I have two servers running ubuntu server 22.04.2 LTS on my local network, the servers have the following names and IP addresses: ubuntuserver100 - 192.168.50.100 and ubuntuserver101 - 192.168.50.101 ...
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ufw rules for Selenium grid
I use Selenium grid docker container on my server which could be accessed from the web by http://IP_address:4444.
Please help me to figure out how can I filter or disable this connection by adding ...
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is there any way to import ufw rules quickly?
just wondering if is there any faster way than this to import ufw rules
i'm trying to block geo ip's and as you know each country have tons of ip's it takes forever to deny access with this method
cat ...
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Block ips from certain country and security
I have an Ubuntu Server 22.04 with Nginx installed along with a laravel application.
When I view the access logs I can see a lot of attempts from a certain country to exploit my server and application....
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Add custom iptables rule to UFW to be persistent
I would like to add the following rule to block the access for a specific user in Ubuntu 22.04 and persist whenever UFW is on. Is there a mechanism to do this while playing nicely with the UFW?
-A ...
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633
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Block access by Geo location
I'm wondering if it's possible to block access based on location, as many hackers and ransomware attacks in recent years came from Russia or Belarus etc.
I dont want my vps accessed by those ...
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SSH configured ports not working
Just installed Kubunut 22.10. I configured my /etc/ssh/sshd_config with a custom port.
# Snip
Port 5555
AllowUsers bob
# Snip
Then restart the daemon to refresh the configuration:
sudo ufw allow 5555
...
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Error establishing a connection to SQL Server
Welcome, After installing MS SQL Server on Ubuntu and trying to connect it shows the following:
~$ sqlcmd -S .\SQLEXPRESS -Q "SELECT GETDATE();"
Sqlcmd: Error: Microsoft ODBC Driver 17 for ...
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315
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Remove internet access from specific applications
I'd like to remove internet access from certain applications like KeepassXC.
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164
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Can't get ssh working on Ubuntu
I am trying to follow this guide to get phpMyAdmin installed on Ubuntu 20.04.
The first step is to set up a non-root user, and it's here that I'm stuck. I cannot log in to root@public_server_ip. I am ...
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