Double Tall Iced Mocha, Lite on the Chocolate

After numerous airline complications, decending through a massive thunder and lightning storm, and a cabin full of applause for the pilots upon landing, I am finally in St. Louis for the National Summit for Community Wireless Networks.

Matt and I spent the last couple of hours at the Waffle House drinking coffee and musing over various topics. One of which included the lack of actual diners in Seattle. I spent a good portion of my teenage years in New Hampshire hanging out at diners drinking cowboy coffee, chatting with friends and watching random people foat through. Its hard to sum up the diner experience in words, but we definately got it at the waffle house.

Better late than never…Some of the hacknight details. Rob discussed the release of Pyramid Linux, a replacement for the aging Pebble Linux that we have all learned to love and loath on embedded hardware. Pyramid is based on a Ubuntu and has all the lastest bits kernel and userland wise.

We also renewed the SSL certificate for the Seattlewireless and chuckled at the Geotrust authentication for aquiring a certificate.

In addition I rediscovered upon updating the cert that Courier IMAP requires that you keep your private key and cert in the same file. While its true that if someone owned my courier server they would probably have access to the private key anyways, it just seems silly and lazy to have to store them both in the same file.

Also Rob posted his account already.

Update: It appears we were overlooking a big thing here, the needed Preferences Pane to actually enable “Wide Area Bonjour”.

Yet another hacknight. Seems that Eric, Rob, and I have spent most of our time trying to advertise services in Bonjour (Apple’s implementation of ZeroConf) via plain old DNS using SRV records. Bonjour, previously called rendezvous is usually associated with Multicast, and Multicast DNS. It sends Multicast DNS requests out the local network to discover services like printers, ssh servers, web servers, and Ichat participants.

It seems that a not so well known fact about bonjour is that it in addition to querying via Multicast DNS, it will also do a unicast DNS request to your default domain.

The basic idea is this. Lets say your default domain is foo.com. You have an SSH server you want to advertise to people in your domain. You create a SRV record to advertise this service and anyone who opens their Bonjour client looking for SSH servers will check their default domain via unicast DNS as well, and if it finds a record it will show it in the Bonjour client.

Sounds easy enough, although finding the right zone file fu has proven difficult. We have figured this out so far:

Domain foo.com needs a ptr record for the service type you wish to advertise.

Domain foo.com also needs a SRV record specifing the name and port of the service.

The Bonjour client then when browsing for SSH servers via Multicast DNS, should also query a PTR record containing the name and protocol (i.e. ssh and tcp) and that PTR record should return the SRV records for the available SSH servers. Of course this can be applied to any abitrary UDP and TCP service. We are just trying to get the bugs worked out using SSH as an example.

Here is a similar example from the Orielly Zero Conf Book:

; Invite clients to browse this domain ("@" means "this domain")
b._dns-sd._udp                  PTR     @
lb._dns-sd._udp                 PTR     @

; Advertise our web page ("www.
" in this example)
_http._tcp                      PTR     Our Web Page._http._tcp
Our Web Page._http._tcp       SRV     0 0 80 www
TXT     path=/

Using this, google, ethereal and stumbling through the rfc draft, we have made some progress but its still not *working* fully.