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+---
+layout: page
+title: Oracle Cloud Instance - Ports opening (Oracle Linux and Ubuntu)
+parent: Community Guides
+nav_order: 9
+---
+
+# Oracle Cloud Instance - Ports opening (Oracle Linux and Ubuntu)
+{: .no_toc }
+
+> **Info about this guide:**  
+> In this guide, I'll only cover the ports management, both on OCI console and on the server itself.
+> Focus will be held for BlueMap access, not your minecraft server or the way to setup it.
+{: .info }
+
+1. TOC 
+{:toc}
+
+
+## Step 1 : Open the ports on your Oracle Instance (web console)
+
+Go to your console ([Oracle Cloud Login page](https://cloud.oracle.com/)), next in the menu, go to "Networking" and then select "Virtual Cloud Networks"
+
+![Screenshot of the OCI web configuration menu]({{site.baseurl}}/assets/ociconf/OCI_01.png)
+
+On the new page, you should see your virtual network (in the form of "vcn-....", by default), select it.
+After that, select your subnet and then, the "Default Security List" (only one of each).
+
+You should get a page similar to this screenshot :
+
+![Screenshot of the default OCI network rules]({{site.baseurl}}/assets/ociconf/OCI_02.png)
+
+Select "Add Ingress Rules"
+The first rule we add is for accessing BlueMap :
+
+![Screenshot of the rule configuration for port opening of BlueMap]({{site.baseurl}}/assets/ociconf/OCI_03.png)
+
+So, as the source, we set it to ANY, so : 0.0.0.0/0
+For the port, if you let the default one : 8100
+The protocol is TCP (standard for HTTP services)
+
+Then, we also need to allow the access to our Minecraft server, if not done yet (depends on which version you installed and/or mods to allow either clients to connect to your Java server)
+
+![Screenshot of the rule configuration for port opening of Minecraft Server]({{site.baseurl}}/assets/ociconf/OCI_04.png)
+
+For all those settings, adapt the destination ports to your needs.
+
+After that, you should have some rules like those ones :
+
+![Screenshot of the OCI network rules summary]({{site.baseurl}}/assets/ociconf/OCI_05.png)
+
+
+Now, a quick explanations here on what we did above :
+
+"Stateless" ==> We do not want to manually create Egress rules, so we do not check this box and let the system handle the connections.
+If we had selected it, we would have needed to create a rule to allow ANY destination to get out of our server from the BlueMap web server port (to any destination port (as this is a random port, never the same).
+
+"Source CIDR" ==> We want to get ANY outside connection to connect to our server, so we specify in CIDR notation, "all", which is 0.0.0.0/0
+
+"Source Port Range" ==> Is defined by the client host (random), so we let this box empty.
+
+"Destination Port Range" ==> For this one, we set to the value of the destination service, in this case for example, the BlueMap port 8100.
+
+
+## Step 2a - Oracle Linux 8
+
+The official guide on how to open your ports can be found there : https://docs.oracle.com/en/operating-systems/oracle-linux/8/firewall/firewall-ConfiguringaPacketFilteringFirewall.html#ol-firewall
+
+But, here is the summary on what you have to do for your Oracle Linux setup :
+
+> **Info:**  
+> All those commands are preceded with "sudo". If you are already using the root account, you can remove it from the command !
+{: .info }
+
+First, check that `firewall-cmd` command is available on your system.
+You can check it's presence with this command :
+```
+sudo firewall-cmd --version
+```
+
+If you don't get a version output or simply "Command not found", do the following commands to install it :
+```
+sudo dnf install firewalld
+sudo systemctl enable firewalld
+```
+The second command ensure it will start on boot.
+
+
+Then, you can simply add the needed ports to the rules list, for BlueMap, it's by default 8100/tcp, so the command will look like this :
+```
+sudo firewall-cmd --permanent --zone=public --add-port=8100/tcp
+```
+
+As a final command, just run this to reload the firewall configuration with your changes
+```
+sudo firewall-cmd --reload
+```
+
+
+## Step 2b - Ubuntu
+
+As per Oracle's Best Practices, follow the steps explained here : https://blogs.oracle.com/developers/post/enabling-network-traffic-to-ubuntu-images-in-oracle-cloud-infrastructure ; At the chapter "Host Firewall".
+
+The method used there is to edit a file named "/etc/iptables/rules.v4" and add your rules in there.
+
+Your file should look like this (the start of it at least) :
+```
+# CLOUD_IMG: This file was created/modified by the Cloud Image build process
+# iptables configuration for Oracle Cloud Infrastructure
+
+# See the Oracle-Provided Images section in the Oracle Cloud Infrastructure
+# documentation for security impact of modifying or removing these rule
+
+*filter
+:INPUT ACCEPT [0:0]
+:FORWARD ACCEPT [0:0]
+:OUTPUT ACCEPT [463:49013]
+:InstanceServices - [0:0]
+-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
+-A INPUT -p icmp -j ACCEPT
+-A INPUT -i lo -j ACCEPT
+-A INPUT -p udp --sport 123 -j ACCEPT
+-A [...]
+COMMIT
+```
+
+You can then insert a new line, for BlueMap, this would look like this :
+```
+# CLOUD_IMG: This file was created/modified by the Cloud Image build process
+# iptables configuration for Oracle Cloud Infrastructure
+
+# See the Oracle-Provided Images section in the Oracle Cloud Infrastructure
+# documentation for security impact of modifying or removing these rule
+
+*filter
+:INPUT ACCEPT [0:0]
+:FORWARD ACCEPT [0:0]
+:OUTPUT ACCEPT [463:49013]
+:InstanceServices - [0:0]
+-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
+-A INPUT -p icmp -j ACCEPT
+-A INPUT -i lo -j ACCEPT
+-A INPUT -p udp --sport 123 -j ACCEPT
+-A INPUT -p tcp -m state --state NEW -m tcp --dport 8100 -j ACCEPT
+-A [...]
+COMMIT
+```
+
+Now, save the file and after that, you can either chose to reboot the server or run the following command :
+
+```
+sudo iptables-restore < /etc/iptables/rules.v4
+```
+
+## Step 3 - Enjoy !
+
+If you did arrive there, you should be able to access your web map with the address : http://Your_Server_Public_IP:Your_BlueMap_Web_Port (port, by default is 8100).
+
+If you want to use a custom DNS and/or HTTPS, you can find some information in the Webserver Wiki ([Reverse proxy BlueMap with NGINX](https://bluemap.bluecolored.de/wiki/webserver/NginxProxy.html))