This article shows how to create a service to define specific ports (5723 in our example) and configure the service in a security policy on Paloalto Firewall so that the server in DMZ can access the server in Trust.
Step 1: Configure the service ports
1.Login PA Firewall and go to Objects > Services
2. Click on Add on the left bottom.
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3. Enter the Name, Protocol and Destination Port.
4. Click OK to save the settings.
Step 2: Create a policy and add the services to the policy
1.Go to Policies > Security
2.Click on Add. Note: you also Clone a current policy.
3. In General, enter the Name, select Rule Type and Tag.
4. In Source, select DMZ as Source Zone and add source address.
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4. In Source, select DMZ as Source Zone and add source address.
5. In Destination, add Trust to Destination Zone and address.
6. In Service/URL Category, add the service ports you configured earlier by clicking Add and then OK to save the settings.
Step 3: Commit.
Please view this step by step video: