DNS-SD configuration documentation

[Matthew MacKenzie <mattm@adobe.com>]

I've attached documentation of steps I took to get DNS-SD working for ebXML Registry.  Comments are welcome.

The configuration is live on the DNS server located at a.ydcorp.com.  Within a couple hours, the server information should be spread across the network, so you can try the commands out yourself if you were so inclined.

Title: ebXML Registry DNS-SD

ebXML Registry DNS-SD Configuration

Matthew MacKenzie mattm AT adobe DOT com

The primary goal of this investigation is to validate that ebXML Registries can be discovered using DNS based Service Discovery, which has been made popular by Apple's Rendevous technology, as well as ZeroConf.

The secondary goal is to allow the configuration to be reproduced easily using ubiquitous tools (BIND, nslookup, dig).

Use case description

Given a domain name, "esd.geek.ca", user needs to be able to:

• Find all ebXML Registries that are available for access.
• Obtain enough information about one or more of the discovered registries, and construct a URL that points to the selected registry's HTTP binding.

Required information

To meet the use case above, we need to store the HTTP Binding URL path in a DNS TXT record, and the actual HTTP port and hostname in a SRV record.

BIND configuration to meet our Use case

/etc/named.conf

/etc/named.conf

options {
        directory "/var/named";
};

zone "." {
        type hint;
        file "named.root";
};

zone "esd.geek.ca" {
        type master;
        file "db.esd.geek.ca";
};

zone "_tcp.esd.geek.ca" {
        type master;
        file "db._tcp.esd.geek.ca";
};

/var/named/db.esd.geek.ca

$TTL 1h
esd.geek.ca.    IN      SOA a.ydcorp.com. matt.ydcorp.com.  (
                                      2004041800 ; Serial
                                      3h         ; Refresh
                                      1h         ; Retry
                                      7d         ; Expire
                                      1d )       ; Minimum TTL
                IN      NS      a.ydcorp.com.

                IN      A       65.39.171.216
                IN      TXT     "Geek.ca ESD"

Entity\032Management    IN      A       65.39.171.216
Entity\032Management    TXT     "HttpBinding=/http-binding"
Entity\032Management    SRV     0 0 8080 mac-kenzie.net.

Partner\032Management    IN      A       65.39.171.216
Partner\032Management    TXT     "HttpBinding=/http-binding"
Partner\032Management    SRV     0 0 8080 mac-kenzie.net.

/var/named/db._tcp.esd.geek.ca

$TTL 1h
_tcp.esd.geek.ca.    IN      SOA a.ydcorp.com. matt.ydcorp.com.  (
                                      2004041800 ; Serial
                                      3h         ; Refresh
                                      1h         ; Retry
                                      7d         ; Expire
                                      1d )       ; Minimum TTL
                IN      NS      a.ydcorp.com.

                IN      A       65.39.171.216
                IN      TXT     "Geek.ca Enterprise Service Discovery"
_ebreg          IN      PTR     Entity\032Management.esd.geek.ca.
_ebreg          IN      PTR     Partner\032Management.esd.geek.ca.

Making the necessary DNS queries

Initial discovery

nslookup -sil -q=ptr _ebreg._tcp.esd.geek.ca

Output:

Server:         127.0.0.1
Address:        127.0.0.1#53

_ebreg._tcp.esd.geek.ca name = Entity\032Management.esd.geek.ca.
_ebreg._tcp.esd.geek.ca name = Partner\032Management.esd.geek.ca.

nslookup -sil -q=any "Entity\032Management.esd.geek.ca"

Output:

Server:         127.0.0.1
Address:        127.0.0.1#53

Name:   Entity\032Management.esd.geek.ca
Address: 65.39.171.216
Entity\032Management.esd.geek.ca        text = "HttpBinding=/http-binding"
Entity\032Management.esd.geek.ca        service = 0 0 8080 mac-kenzie.net.

From these two queries, we have everything that is needed to connect to the server's HTTP binding. Host, Port, HTTP path.
___________________________
Matthew MacKenzie
Senior Architect
IDBU Server Solutions
Adobe Systems Canada Inc.
http://www.adobe.com/products/server/
mattm@adobe.com
+1 (506) 871.5409