What does ".local" do?

Question

I've got several Ubuntu machines on my network at home, but the DNS is provided by a windows server (2K). When I ssh to them from another , if I ssh to them as "machine" I can't connect, but if I connect as "machine.local" I can connect.

I think similarly, I can't connect from a windows client (like putty).

What's going on here? - it's clearly an Ubuntu thing.

Solution

To fix your issue, you just need Avahi. This announces your Ubuntu machine names to the Windows lot.

sudo apt-get install avahi-daemon

machinename.local works thanks to another implementation of zeroconf (of which Avahi is also) called Bonjour, created (IIRC) by Apple. It's installed by default. I don't know why Avahi isn't also but given the confusion it causes people, it probably aught to be.

There's more on this on Wikipedia: http://en.wikipedia.org/wiki/.local

Comments

[Admin]

Actually, it looks like a DNS thing, not like an Ubuntu thing at all (especially since you “can't connect” from the Windows machine — and what is the error message anyway?). What is your DNS configuration (nameserver and search)? How does dig machine1 differ from dig machine1.local?

[Admin]

Would you happen to have Apple Bonjour or another Zeroconf implementation installed on the Windows 2000 Server?

[Admin]

If you happen to know why Android can't browse to a device on the network using its .local hostname (devicename.local does not work but it can browse to devicename without .local), I'd appreciate an answer at android.stackexchange.com/q/230644/22600 Thanks!

[Broam]

Avahi uses .lan I think

[Kees Cook]

No, avahi uses .local, this is required by the mDNS spec.

[Admin]

Avahi Link for the interested. In short, its complicated.