Turn off IPv6 via command line?

Only if you can figure out how to use the defaults command appropriately. The info is stored in the /Library/Preferences/SystemConfiguration/preferences.plist file. However, why bother when it's so simple to use the Network prefPane under System Preferences? BTW, Unix queries belong in the Unix forum under OS X Technologies.

Brian S. Campbell wrote:
is it possible to turn off IPv6 via the command line?

Maybe this will do enough...

network.dns.disableIPv6 user set boolean true

What exactly is

*network.dns.disableIPv6 user set boolean true*

intended to do? Are you suggesting using defaults with this? Do note that there are four settings for IPv6 in that plist I referenced and AFAICT, your command is incomplete and won't work as you envision.

Then, experiment with the defaults read and write commands on a copy of that preferences.plist file in /Library/Preferences/SystemConfiguration/ and see if you can figure out the specifics. AFAICT, IPv6 is OFF by default in Snow Leopard. Alternatively, if you're using a master OS for deployment, fix that instead.

There you go. Thanks for the feedback. Good computing.

baltwo wrote:
AFAICT, IPv6 is OFF by default in Snow Leopard.

I disagree with your line regarding default IPv6.

I just bought nearly 80 Snow Leopard iMacs and net MBpros and IPv6 was enabled on every single one (and still is). So I'm basically saying that a command-line fix that doesn't interrupt the user is much nicer than saying, "Opps Apple goofed on shipped computers and I need yours back."

Hopefully the defaults jazz works but its strange why Apple support never publishes a complete CLI client compendium. BTW, the 10.6 Server CLI Tools manual is a fraction what the 10.5 CLI Tools manual was.

I should also say that I have used 'networksetup -setv6off "Built-in Ethernet"' for 10.5 iMacs and 'networksetup -setv6off Ethernet' for 10.6 iMacs, MacPros, and Macbook Pros.