A firewall is a network-based service that blocks all unpermitted traffic, following a set of applied rules.

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  • 20 Results
    • Tutorial

      Recommended Security Measures to Protect Your Servers

      When setting up infrastructure, getting your applications up and running will often be your primary concern. However, making your applications to function correctly without addressing the security needs of your infras...
      7 days agoBy Justin Ellingwood, Alex GarnettSecurityFirewallConceptualNetworkingVPN
    • Question

      ERR_CONNECTION_REFUSED when i want to deploy a war file to tomcat

      Hi all, I downloaded tomcat in ubuntu and MySQL database so tomcat runs successfully with my server IP address and the port, and when I want to deploy the war file of my application it gives me “ERR_CONNECTION_REFUSED”
      1 answer12 days agoBy tselawe706APIDigitalOcean Cloud FirewallsFirewallInitial Server SetupUbuntu
    • Tutorial

      How To Set Up a Firewall with UFW on Ubuntu 22.04

      This tutorial will guide you through setting up a firewall with UFW on Ubuntu 22.04.
      1 month agoBy Brian Boucheron, Jamon CamissoFirewallNetworkingSecurityUbuntuUbuntu 22.04
    • Tutorial

      How To Install and Secure Memcached on Ubuntu 22.04

      In this guide, you will install and configure a Memcached server. You’ll also add authentication to secure Memcached using Simple Authentication and Security Layer (SASL). Finally, you’ll learn how to bind Memcached t...
      1 month agoBy Jamon CamissoCachingFirewallInteractiveSecurityServer OptimizationUbuntuUbuntu 22.04
    • Question

      Better k8s firewall control

      Are there plans to allow for better k8s firewall management? It looks like fw is auto-generated when k8s clusters are created. I’d like to create my own with its own rules and have them auto-assign (or manually-assign...
      1 answer1 month agoBy EthanDigitalOcean Cloud FirewallsDigitalOcean Managed KubernetesFirewallKubernetes
    • Question

      Droplet Web Console blocked by UFW - Need rule info like IP range

      Title describes the problem. I installed the console but it times out waiting for handshake. I have UFW (iptables) configured to only allow specific hosts access on port 22. Is there an IP range for DO I can add to ge...
      1 answer2 months agoBy jhargisDigitalOcean DropletsFirewallInteractiveNetworkingSecurity
    • Tutorial

      How To Setup a Firewall with UFW on an Ubuntu and Debian Cloud Server

      Learn how to setup a firewall with UFW on an Ubuntu / Debian cloud server.
      2 months agoBy Shaun LewisFirewallSecurityIPv6UbuntuDebian
    • Question

      Completely block IP from accessing server and postgresql

      Hi, OS - UBUNTU 20.04 Problem: Recently our server and database (postgresql) being attacked by specific IP ( The IP keep on trying to connect to our database and we believe subsequently cause our postg...
      1 answer2 months agoBy CuteGreenBlueMantaRayFirewallPostgreSQL
    • Question

      Ubuntu 20.04 Server - Should I Install Anti-Virus Software?

      I’m running Ubuntu 20.04 Server on my droplet along with Nginx. Should I install anti-virus software like ClamAV as in the following link? Is it essential or recommended? I’m also utilizing a fw and Cloudflare DNS pro...
      Accepted Answer: Hello there, It is essential to secure your droplet, however running malware software is not definitely a must, but it is still a good thing to do. I’ll highly recommend checking our tutorial An Introduction to Securi...
      3 answers2 months agoBy mpasqualiDigitalOcean DropletsFirewallUbuntu 20.04
    • Tutorial

      How To Forward Ports through a Linux Gateway with Iptables

      NAT, or network address translation, is a general term for mangling packets in order to redirect them to an alternative address. Usually, this is used to allow traffic to transcend network boundaries. A host that impl...
      3 months agoBy Justin EllingwoodFirewallUbuntu
    • Tutorial

      How To Implement a Basic Firewall Template with Iptables on Ubuntu 20.04

      Implementing a firewall is an important step in securing your server. In this guide, you’ll learn how to construct a firewall that can be the basis for more complex rule sets. This firewall will focus primarily on pro...
      3 months agoBy Jeanelle Horcasitas, Justin EllingwoodFirewallUbuntuUbuntu 20.04
    • Question

      Port 3000 is closed and not listening

      I installed plesk on ubuntu, my project works with port 3000 and other ports which needs to be enabled and also listens, but i am finding it difficult to find out how to really open it and get it to listen. Here is wh...
      2 answers3 months agoBy Mac ArthurApacheDigitalOceanFirewallUbuntu
    • Question

      UFW Config (easy question)

      Can I explicit allow DigitalOcean console access via ssh without opening my droplet’s 22 to the entire internet? AKA does the console exist on the 10.x.x.x subnet or another entity I can whitelist.
      2 answers3 months agoBy SmallNavyMorelConfiguration ManagementFirewallUbuntu 20.04
    • Question

      Block access in India

      Hello everyone, my website is currently selling to customers all over the world, but now the Indian market has many people entering SEO Spam, not real customers. So what if I want to temporarily block Ind...
      2 answers3 months agoBy bietduocDigitalOcean Cloud FirewallsFirewall
    • Question

      Block Russia Access

      How can I block all my servers access from Russia?Do you have a magic button? Regards.
      1 answer3 months agoBy Alfredo RamirezDigitalOcean Cloud FirewallsFirewall
    • Question

      Can I use DO private networks work to limit ssh access

      I’ll be creating six Droplets (Debian) with both UFW and DO firewalls all to run a copy of a web service. I will also create one droplet to manage these servers. Can I set the firewalls for the servers to accept incom...
      2 answers3 months agoBy bryangilbertDigitalOcean Cloud FirewallsFirewallNetworking
    • Tutorial

      How To Create Rules, Timelines, and Cases from Suricata Events Using Kibana's SIEM Apps

      In this final tutorial in the series, you will create custom Kibana rules and generate alerts within Kibana’s SIEM dashboards. Once you have rules in place and understand where and how to filter Suricata’s logs using ...
      3 months agoBy Jamon CamissoFirewallNetworkingSecuritySuricataUbuntu 20.04
    • Question

      DigitalOcean Firewall + fail2ban

      I’m using the digitalocean firewall, I would like to know if is necessary to use fail2ban too?
      3 answers3 months agoBy LargeLightCyanAxolotlApacheDigitalOcean Cloud FirewallsFirewallUbuntu
    • Question

      Port Ranges Set to DENY in UFW (Firewall) are Still Allowing Traffic on Those Ports

      Here is a screen grab of ‘grep “Failed password” /var/log/auth.log’for reference: I have the port range 30999:59999 set to DENY IN from ANYWHERE for udp and tcp traffic, yet I’m still recei...
      1 answer4 months agoBy AustinFirewallUbuntu 20.04
    • Tutorial

      How To Build A SIEM with Suricata and Elastic Stack on Rocky Linux 8

      The previous tutorials in this series guided you through installing, configuring, and running Suricata as an Intrusion Detection (IDS) and Intrusion Prevention (IPS) system. You also learned about Suricata rules and h...
      4 months agoBy Jamon CamissoRocky LinuxRocky Linux 8SecurityNetworkingFirewallElasticsearchSuricata