Monitoring Network Interfaces

Network Identification Mode
In this tutorial, we share our views on proper use of network interface identification modes, and which active network interfaces should be monitored by dDNS Broker. Please note that, almost always, there are multiple "correct" setups for your network configuration and usage model. Arguably, our recommendations are the most intuitive ones.

The picture above shows active network identification mode selection controls in the "Settings…" window. These modes and their characteristics are summarized in the table below.
Identification ModeDescription
System Default Only
  • Very simple, easy to understand and use
  • Only one network interface, the system default, is identified and monitored
  • Other network interfaces can be active, but only one of them will be the system default interface as determined by the operating system
  • Ideal for Macs with one or very few active network interfaces with static network configuration
Networks by Name
  • Intuitive, easy to understand and use
  • Active network interfaces are identified by their names
  • Third party (non-native) VPNs are identified as "NonNativeVPN"
  • Each active network interface can be monitored independently
  • Unique sets of service records can be specified for each active interface
  • Operating system actions (like resulting default interface) are reflected on the header rows
  • Ideal for Macs with few active network interfaces that are updated occasionally.
Networks by Signature
  • Complex and powerful. For networking savvy users
  • Fine grain identification and management of active network interfaces
  • Each active network interface can be monitored independently
  • Unique sets of service records can be specified for each active interface
  • Operating system actions (like resulting default interface) are reflected on the header rows
  • Ideal for Macs on the move - either physically, or virtually
  • Active network interfaces are initially listed with their network names on the header rows, but these descriptions can be edited by the user to clearly identify the active network interfaces, like; "Wi-Fi (Home)", "Wi-Fi (Work)"
  • Third party (non-native) VPNs are initially listed as "NonNativeVPN". The network signatures used for non-native VPNs are experimental and may be imprecise at times. These signatures are unique per VPN service (like AzireVPN-SE) and not the VPN Client used to connect. Hence, these descriptions should be edited to clearly identify the VPN services they are connected to, like: "NonNativeVPN (AzireVPN-SE)"

Mode Selection and Monitoring Guidance

The most common configuration: One active network
The vast majority of our customers operate a web and/or email server at their home. Most of them utilize a single network interface, like: "Wi-Fi", or "Ethernet", to connect their server to local subnet and router. If you are one of them, select the "System Default Only" mode and monitor the "System Default" network interface.

You have one active network, but occasionally connect to a VPN service:
So, you utilize Virtual Private Network (VPN) connections once in a while. Please be aware that when you are connected to a VPN, especially when using a third-party VPN client, that VPN interface is likely to become your "System Default" network interface. It is best to select the "Networks By Name" mode, and monitor your main network interface (say; "Ethernet"). Also, please make sure that the active VPN interface is not monitored.

You have two active network interfaces:
You use one of the networks (say, Ethernet) to connect to your router, and the other network (say, Wi-Fi) to access other resources on your subnet. You should select the "Networks By Name" mode, and monitor the active network interface that connects your server to your router, in this example, the Ethernet. Please disable monitoring for the second network, in this example, the Wi-Fi network interface.

We hope you found your network configuration and usage model in one of the paragraphs above, and you are curious about what else you can do with IP Monitor. Great, keep reading...

What is there to serve?
To get a sense of which publicly accessible services can be provided on your Mac, lets look at some of the services supported by a popular Mac application, the OS X Server: WebDAV, FTP and SFTP, Mail, Calendar, Contacts, Messages, Websites, Wiki, and VPN. Can you imagine providing one or more of these services on some network interfaces, and a different set of services on other network interfaces? If the answer is yes, then configuring accessibility on different networks is easy and intuitive with IP Monitor.

Usage Model Examples:
Some server usage model examples and their recommended setup guidelines are provided in the table below.

Usage ModelSetup Guidelines
Your iMac is connected to your router with an Ethernet cable, and you host your website.Select the "System Default Only" mode, and monitor only the "System Default" network interface. The dynamic DNS update records must be specified for the "System Default" network.
Your iMac is connected to your router over a Wi-Fi network interface, and you host your email.Select the "System Default Only" mode, and monitor only the "System Default" network interface. The dynamic DNS update records must be specified for the "System Default" network.
Your iMac is connected to your router with an Ethernet cable, you host your email over Ethernet network interface, you use a different hostname for your blog and host it over a native VPN network interface.Select the "Networks By Name" mode, and monitor the Ethernet and VPN network interfaces, setup dynamic DNS update records for your email and blog hostnames on their respective network interfaces.
Your MacBook Pro is connected to your router over a Wi-Fi network interface. You host your WebDAV server only on your friend’s place to share files.Select the "Networks By Signature" mode, when connected to Wi-Fi at your friend’s place, edit the network description to "Wi-Fi (WebDAV)", select monitor on the "Wi-Fi (WebDAV)" network, and setup dynamic DNS update records for WebDAV hostname on "Wi-Fi (WebDAV)" network interface.
You only host a FTP server on your MacBook Pro. You connect to internet over an Ethernet cable at home, over Wi-Fi at work, and over VPN when traveling internationally.Select "Networks By Signature" mode, enable monitoring on "Ethernet (Home)", "Wi-Fi (Work)", and "VPN (Away)" network interfaces. Setup dynamic DNS update records for FTP hostname for the "Ethernet (Home)" network interface. Export your services from the "Ethernet (Home)" network, and import into the "Wi-Fi (Work)" and "VPN (Away)" networks.
Configuring for multiple networks
So, you decided to host multiple services accross multiple network interfaces. Now, let’s look into configuring your domain, your server, and dDNS Broker to achieve the desired results.

  • You need to use unique hostnames for each service, like www.yourdomain.com for web server, mail.yourdomain.com for email server, and webdav.yourdomain.com for WebDAV server. Login to your dynamic DNS service provider and create those unique hostnames.

  • You need to configure your services to bind to different networks. For example, OS X Server allows you to bind different networks to different services. Please refer to your services’ documentation for details.

  • In the dDNS Broker preferences dialog, select each network interface and create dynamic DNS service record(s) for the corresponding hostname(s) you created in the first step.

 Tutorials