Questions tagged [firewall]
a technological barrier designed to prevent unauthorized or unwanted communications between computer networks or hosts
1,242
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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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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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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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Block a spcific subset range in UFW
I am looking to block a specific range in a single line .. Is that possible with UFW?
I'd like to block 1.1.0.0 - 1.1.31.255, but the only way I've found to do so is to put 32 individual rules in IE
$ ...
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How do I install firestarter on ubuntu 22.04.1?
I use this distro, and I've tried sudo install but it says that the package was not found.
Tried through synaptic and also not found.
Has it been discontinued?
2-Is there a better front-end firewall?
...
user1554772
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connection to service with disabled firewall fails
i am trying to access a service on my ubuntu server 20.04
the following command on the local machine:
nc -zv 127.0.0.1 9256
Connection to 127.0.0.1 9256 port [tcp/*] succeeded!
the same command from ...
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Port 3003 is not working while ports 3000 - 3002 are working fine
I have several node.js apps on an Ubuntu server working just fine on ports 3000 - 3002. Now I added one more app to port 3003 and it is not working anymore. I switched the apps on port 3002 and 3003 ...
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I can't reach my server
I have ubuntu 20.04 server hosting with nginx. My site is in word press. I was trying to install ftp by following documentation on Vultr. Suddenly, the connection with my site, lost (502 bad gateway)....
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How to find out the program from iptables log
Testing the ping on ubuntu 22.04:
Host A IPv6: 1111:1111:1111:1111:1111:1111:1111:1111
Host B IPv6: 2222:2222:2222:2222:2222:2222:2222:2222
Host A:
Now execute a ping from Host A with the following ...
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easy firewall ufw settings for a beginner coming from windows [duplicate]
I am used to firewall on windows. everything is allowed and new apps have to ask for permission.
when I look at current connections in settings' firewall tab, only a few have program names associated ...
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Install outline VPN on a NAT VPS
I'm trying to install outline on my NAT server, but I keep getting this error:
Your Outline Server was installed correctly, but we are not able to connect to it. Most likely this is because your ...
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I need a simple TCP load balancer in Ubuntu
I would like to create a load balancer for RDP connections only, that’s one TCP port only and would like to avoid anything more complex like Nginx.
I don’t need cache, or anything else, just take an ...
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I am receiving Dozens of [UFW BLOCK] Messages each second on my syslogs server
I have a Ubuntu server running currently that has suddenly seen a striking drop in incoming traffic after many months of a high average. I have noticed in my logs that dozens upon dozens of UFW Block ...
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ssh: connect to host ********* port 22: Connection timed out
I have Ubuntu 22.04 newly installed on my laptop. I am trying to connect to a remote server and getting the following error:
ssh: connect to host ********* port 22: Connection timed out
I tried some ...
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DDoS Attack - Iptables bad configuration
I have Ubuntu 20.04.4 LTS. I am under a DDoS attack and don't know how to limit the connections made by multiple IP's (avobe 500).
I saw some post, like this or this, but don't know how to follow the ...
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Unable To Connect To Internet Sites Via Live USB - Wi-Fi Settings Are Correct
I was running my Ubuntu Live via USB for the first time. All of my Wi-Fi settings were correct and I was able to get a DHCP address on my network but I was unable to get to any Internet URL including ...
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Your Outline Server was installed correctly, but we are not able to connect to it
I'm trying to config Outline VPN and
I bought a Droplet from Digitalocean with Ubuntu 22.
So, my server generated URI string correctly:
CONGRATULATIONS! Your Outline server is up and running.
To ...
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Why am I able to connect to Wi-Fi(router) without any issues while all the In/Out traffic is blocked with UFW
When I block all the traffic with ufw, e.g.:
ufw default deny incoming
ufw default deny forward
ufw default deny outgoing
I can't receive or send anything, but I still able to connect to my home Wi-...
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Can't access Ubuntu Server with SSH after doing something with iptables
I'm trying to run a MC-Server on an Ubuntu Sever (Oracle Cloud). I already port forwarded 25565 and 22 but still couldn't access the server. I found these commands on another tutorial, but when I ...
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iptables/ ufw problem with getting emails
I have a very difficult problem that I can't seen to solve.
I have an Ubuntu Server 20.04.5 LTS set up as a firewall/ router, so it has two interfaces. One internet connected and the other lan ...
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My Ubuntu Server Ports got locked
I just tried to join to my Jenkins on my VPS as usual. When I try to access the URL it returns the error code ERR_CONNECTION_TIMED_OUT. This happens as well with port 8080 for my website and other ...
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DNS only works when I have a port 53 UDP outbound rule *AND INBOUND* rule
I'm locking down both inbound and outbound ports with
iptables -P INPUT DROP
iptables -P OUTPUT DROP
Then, I allow certain traffic to certain servers
SSH from my network to the server (inbound)
HTTP ...
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Should I be concerned about these UFW blocked traffic?
I just installed ufw on a newly provisioned Ubuntu 22.04 Server. It is currently set up to deny all traffic except ssh on an alternate port.
I'm getting this pattern of blocked traffic:
Oct 6 10:09:...
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DNATing DNS requests that aren't going to a particular server. iptables : No chain/target/match by that name
I have some chains that I create in iptables
iptables -N dns-requests
iptables -N wg0-filter
I then create a filter, to pass DNS traffic that are on Port 53.
iptables -A wg0-filter -p tcp --dport 53 -...
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ufw not logging on ubuntu 22.04
I have no ufw logs on my minimized Ubuntu 22.04 server.
sudo ufw status verbose output:
$ sudo ufw status verbose
Status: active
Logging: on (low)
On the internet I found I need rsyslogd enabled. On ...
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Ubuntu 20.04 Server UFW does not activate automatically
Lately, I've noticed that UFW is inactive until I activate it manually.
I've run ufw enable multiple times, checked that ufw.service is active, but it still does not start on boot.
Output of systemctl ...
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How to disallow connection by ip country except one?
I want to disallow incoming connection from all country except one.
I know https://www.ip2location.com/free/visitor-blocker and what files I have to download and allow and select 1 country.
Then how ...
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usg ufw conflict rules
I ran a usg audit (following https://ubuntu.com/blog/cis-security-compliance-usg)
sudo usg audit cis_level1_server
See audit result here
I don't understand what usg is trying to do with ufw.
First, ...
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ufw Does Not Block Port for curl
I am trying to block outgoing traffic to port 9200 temporarily. My use case is I want to test what happens when an Elasticsearch cluster (at port 9200) becomes unreachable to my application.
I ...
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Why Can't I access my website ,even if 80 port of my ecs server is open?
os system of ecs server :ubuntu.
os of my computer:win10.
I deployed my web project to my ecs server. I could access my project online until I installed the ufw on my ecs server. I cofigured the ...
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Can't use Firefox on Ubuntu 22.04.1 LTS on Lenovo ThinkPad T460 after installing and uninstalling Proton VPN
I installed ProtonVPN. It worked for a while with Firefox. Then ProtonVPN started to send "not responding" error messages. Though the internet is fully operational on all other devices, ...
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Questions re ufw settings
I have been running Ubuntu 20.04 desktop since last February, and I configured and enabled ufw at that time. I have questions on the output below.
sudo ufw numbered
To ...
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Translate iptables rule to UFW
I need to translate these rules:
iptables -A firewall -p udp –dest 239.250.0.0/16 -j ACCEPT
iptables -A firewall -p igmp –dest 239.250.0.0/16 -j ACCEPT
To UFW rules. Don't know how to set -A -dest -j....
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UFW ALLOW rules not working and being ignored
We're setting up some zero trust environments and are needing to block all incoming and outgoing ports, except for allowing the office IP to go in (for administrative purposes), and port 80 and 443 to ...
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Ubuntu server behind a firewall
I have a problem regarding a server behind a firewall, essentially, the whole internet is blocked, and I can't use the "add-apt-repository", problems like "X user or team does not exist&...
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"Failed to start" notifications when booting into Ubuntu
When attempting to boot I get the following messages:
Failed to start Set the console keyboard layout
And
Failed to start Uncomplicated firewall
The screen has remained the same for about 30 minutes ...
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22.04 - ufw/ip tables could not fetch rule set
I'm trying to get UFW up and running on a Raspberry Pi 4 running Ubuntu server 22.04. But I am at a loss.
# via SSH session:
~$ sudo ufw status
ERROR: problem running iptables: iptables v1.8.7 (...
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How To Permanently keep port 80 open On Ubuntu Server
I just installed Ubuntu Web Server and at the end of the install, it mentioned to me that I could go to IP address. Did that and got the great saying "can't connect". I figure port 80 didn't ...
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Port 9000 Open in FW But Not Showing In NMAP
I am running an Ubuntu 20.0.4 LTS virtual server.
I need to be able to access http://localhost:9000/ from within the server for a service I am trying to run, but I keep getting 'Connection refused' ...
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Ubuntu server 22.04 VM Openvpn connection issues
I'm currently working on a homelab project and built a home server using VMWare ESXI 7. On this Hypervisor i run two ubuntu 22.04 server images, one for file sharing and one to serve as a vpn server.
...
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527
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Cannot access to the remote Linux server after activating firewall
I accidentally log out from my remote Linux ubuntu server after enabling firewall. When I am trying to connect with my SSH it gives me 'port22: operation timed out'. Is there any ways to connect to ...
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accepting request to connect on DB port only from a DNS
I'm trying to add an INPUT rule to my server so that only specific address can connect to my DB.
So far I tried this
iptables -A INPUT -p tcp -m string --string dnsname.com --algo bm --dport 5432 -j ...
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2
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Unexpected entries in firewall log (ufw)
Background
I recently installed Ubuntu 22.04 LTS desktop. I left all the default settings untouched during installation, and additionally installed google-chrome and VLC.
The machine is behind a ...
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