MacOS – Location-aware hostname resolution

macbook promacosNetworkvpn

Here is my situation: I am running Tunnelblick on my MacBook (running Mavericks) to connect to my own VPN, which comprises several machines, both at home and at remote locations. I can of course use the VPN-internal addresses to enable communication between my MacBook and other machines but I would like to prefer local addresses for a machine, if possible.

Example:

I have a server that is running an AppleTalk daemon for Time Machine. This server is part of the VPN and as thus it’s reachable under a 10.x.x.x IP address. However, when I’m at home I would like to use the local 192.168.x.x IP address so that traffic doesn’t have to go over the internet (and my rather smallish outbound bandwidth). Currently I edit /etc/hosts every time I arrive at the office or at home to facilitate the switch.

Is there any way to have this switch happen automatically?

Best Answer

Maybe ControlPlane can help you.

ControlPlane allows you to build configuration profiles, contexts in ControlPlane lingo, for your Mac based on where you are or what you are doing.

ControlPlane determines where you are or what you are doing based on a number of available evidence sources and then automatically reconfigures your Mac based on your preferences. Evidence sources can include your current location, visible WiFi networks, attached USB devices, running applications and more. You can even write your own evidence sources using shell scripts!

Related Solutions

MacOS – VPN Changes Hostname

The VPN's DHCP server probably assigns hostname together with the IP address and the computer uses it instead of what you've set during setup and what appears in System Preferences -> Sharing -> Computer name.

To set a permanent hostname do sudo scutil --set HostName DesiredHostname in Terminal.app (there are also ComputerName and LocalHostName that can be changed there). Restart may be required.

MacOS – Why is the hostname resolution taking so long

I was able to fix this issue by explicitly setting the HostName using scutil to be the same value as LocalHostName:

$ scutil --set HostName $(scutil --get LocalHostName)

Now:

$ sudo scutil --set HostName MacBook-Pro
$ time python -c 'import socket; print(socket.getfqdn())'
MacBook-Pro
python -c 'import socket; print(socket.getfqdn())'  0.01s user 0.00s system 86% cpu 0.016 total

I was confused before because of the following:

$ scutil --get LocalHostName
MacBook-Pro

$ hostname
MacBook-Pro.local

But:

$ scutil --get HostName
HostName: not set

Best Answer

Related Solutions

MacOS – VPN Changes Hostname

MacOS – Why is the hostname resolution taking so long

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