If I am configuring a gatekeeper cluster of 2 gatekeepers, and I have 3 local zones on the gatekeeper, how do endpoints that register to the gatekeeper choose what zone to go in?
Can you have multiple 'local' zones on a single gatekeeper?
In gatekeeper call routing we have something like yes or no terms that is how a gatekeeper will route a call based on an incoming Admission Request message (ARQ) message
Start:E.164 number match-yes-Target zone=matched endpoints zone- via zone processing -send ACF
Tech-prefix match-yes -strip the tech-prefix-hop-off tech prefix - targetzone=hop-offzone
ZONE-PREFIX match-Is arq reject-unknown prefix set? -send ARJ
Target zone=matched zone
Here are the good documents;
The behavior of a gatekeeper when it processes a call request in the form of an admission Request (ARQ) from an H.323 endpoint.
As machin explained to you dialed number will match a prefix and it tie you to a zone, but I think you are asking about endpoint registration don't you?
So if that is the case you can use "zone subnet" this way you configure a zone for a diferents kinds of devices based on the subnet it belongs, so is very important you use no on front of zone subnet also, this way you clear specify to wich zone this device no attempt to register to a no desired zone.
Check SRND for Cisco unified Communications Example( http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/7x/video.html#wp1045804)
Section Gateways Zone prefixes/ZOne Subnets.