Questions tagged [firewall]
a technological barrier designed to prevent unauthorized or unwanted communications between computer networks or hosts
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Is there anyway to block/whitelist certain ASN number on Ubuntu?
I knew how to configure ufw or (iptables), but how do I whitelist certain ASN number on Ubuntu?
lsb_release -a
Distributor ID: Ubuntu
Description: Ubuntu 20.04.6 LTS
Release: 20.04
Codename: ...
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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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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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Ubuntu Server Port 443 closed, Docker application not accessible in local network
I am using Ubuntu Server Ubuntu 22.04.2 LTS in my homelab (esx Server) to test some docker applications. First of all I was testing Bitwarden, a webbased Password-Manger. Without any success. I could ...
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firewalld / ufw defaults - firewall access
I am using ub 20.0.4.2 - a pretty standard load to play with.
vm was a standard load, 4 nics (eth0, eth1, eth2, eth3) with fixed IP / 8gb. and eth0 goes to the gateway, and DNS is 9.9.9.9
Installed ...
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Redirect traffic between LAN and OPT1
In Pfsense, I have two network cards, one connected to a network 192.168.56.2 which is the LAN network and the other one is connected to the network 192.168.58.2 which is the OPT1 network; these are ...
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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 ...
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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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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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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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Bridging 4 ports together as a switch, then connecting them to the outside world with a 5th port
The setup:
Ubuntu 20.04 box with 5 physical ethernet ports (let's call them eth1 - eth5).
What I'm trying to do:
Configure eth2-eth5 as a switch, so they can all talk to each other without ...
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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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How to block more than 3 ping requests from a host through iptables?
i want to block more than 3 ping echo-requests for demonstration purpose of my college practical, and i am unable to do so using the following rules in my firewall.
iptables -A INPUT -p icmp --icmp-...
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Can't access to express backend apis which is running on ubuntu server
I established backend on Ubuntu 20.04 with pm2 command.
Here is the log when I use yarn start:
pm2 launched in no-daemon mode (you can add DEBUG="*" env variable to get more messages)
2023-...
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98
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UFW not blocking ip
I have ubuntu 22.04 and have tried to block an ip as follows:
sudo ufw deny from 109.237.96.124 to any
I run ufw status which give me the following:
To Action From
-- ...
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Cant reach opened port on Oracle ubuntu
like i wrote in topic, i cant reach opened port 25565 but i can reach opened port 4000 like below. On port 4000 i have nomachine service and everything works fine.
PS C:\Users\WONSZ> Test-...
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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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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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Remove internet access from specific applications
I'd like to remove internet access from certain applications like KeepassXC.
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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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Firewall losing state on LAN connection interruption?
Could you please help me with the following issue?
Have an established SSH connection, but it goes down right after my LAN connection gets interrupted for few seconds and firewall starts blocking it. ...
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firewalld doesn't allow outgoing connections
My (really) old firewall died and I decided to replace it with Ubuntu 22.04 as I have moved to it on my other servers as well.
I have two NICs, one (en2ps0 X.X.X.X, zone public) for outer world and ...
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NFTables and g(ufw)
I am going to install Xubuntu 22.04 on one of my computers and i have a question about firewall.
As i understand Ubuntu use NFTables now.
I have noticed some information about Debian (which is base ...
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VPN "Kill Switch" Without Hard-Coded IPs
I'm using a popular VPN provider, and I downloaded their OpenVPN configs. In total there's probably >100 different server IPs specified in these configs. Is there a way to configure Ubuntu 22.04 ...
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How to enable a specific port on Ubuntu version 22 so that it is accessible to outside world?
How to enable a specific port on Ubuntu version 22 so that it is accessible to outside world?
I am already logged into the server through ssh using port 22 and able to successfully execute all the ...
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Make port 80 globally accessible
I am trying to set up a VPS server (Ubuntu 22.04 LTS) bought from Microsoft. I am able to set up NGINX on my own by watching this tutorial. After setting up all the configs stated in the video I ran ...
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Not able to run application using external IP in GCP
I have set up an ubuntu 18.04 machine with 16 gb memory in GCP.
Have reserved a static address and created a firewall rule where i have allowed TCP port 8888.
IP range i have given 0.0.0.0/32.
...
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mount network drive through VPN kill switch - Ubuntu 20.04 Synology DSM 7
I know this has been asked before but nothing I try has worked. Any suggestions are appreciated!
I am trying to mount a network drive on Synology NAS 5.7 to my Ubuntu 20.04 server. If I disable ufw ...
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iptabels firewall rules for INPUT while Tor traffic on lubuntu 22.04 LTS
i do have lubuntu 22.04 LTS and TOR daemon with the torrc config
VirtualAddrNetwork 10.192.0.0/10
AutomapHostsOnResolve 1
TransPort 9040
DNSPort 9053
and iptables rules
#exclude locals
TOR_EXCLUDE=&...
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UFW - Default Deny Incoming does not block telnet
I have an Ubuntu 22.04 LTS Server setup on a VM. I have ufw enabled with default deny incoming policy
The result of sudo ufw status verbose is:
Status: active
Logging: on (low)
Default: deny (incoming)...
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72
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Login with firewall enabled leads to black screen
I am using Ubuntu 22.04 LTS with desktop running on Xorg.
I wanted to do some work on my notebook today, so I got up, booted the computer, logged in and stared at the black screen for a while. After 5 ...
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How to drop an existing connection on Ubuntu 20.04 server?
I executed the following command to ban them. But it didn't work. It only works when there is a new connection from that IP.
sudo ufw insert 1 deny from 46.1.67.244 to any && sudo ufw reload
...
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iptables to block http and ssh in one direction
I have a topology where there is a Linux as a router that connects two Linux, and I want to use iptables to filter ssh and HTTP in one direction.
I used the below code but it didn't work!
I really ...
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Iptables and route2 to achieve multiple WAN IPs
Debian based machine with 1 wireless NIC.
That would be wlan0, tap1 and tap2 (both tap installed with tuntap). tap1 and tap2 have their own MAC addresses and public IPs set.
I have removed all the ...
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Using Ubuntu as a Redirector
I have a question that I hope is simple, but I can't seem to find an answer.
I have an Ubuntu server that only allows connections from one specific source IP address. This IP address belongs to ...
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Limit parallel active connections per ip
So basically we are providing an API, where people connect remotely.
The idea is to deny everyone the access/ping to the IP of our server, except the whitelisted people (which are our customers). I ...
