Your granite fabricator will mount the sink for you. Where I am (the South) the standard is 3cm stone with no plywood underlay, so all undermount sinks are attached directly to the stone. Sometimes it is just adhesive. Other times there are bars or a support cradle that is drilled into the stone. You'll have to ask your fabricator how it will be done, taking into consideration the specs for the particular sink you have chosen.

Using angle iron you can anchor into the cabinet sides.
Many companies sell "brackets" that you can buy as a ready made product.
Braxton-Bragg is one,

Don't ever expect any anchoring into the stone counter to be good.
Drilling holes is not a good thing. It promotes cracking.
Siliconing is not a good thing. As leakproofing it is good. It is not structural.

Use the Sink Setter to support ANY undermount sink from underneath.....

They NEVER fail!!!

I have been using them for the last 10 or 12 years now with 100% success

hth

kevin

Here is a link that might be useful: Sink Setter Web Site

Fantastic. I like the sink setter and some products by braxton-bragg, in particular, the peel and stick...though I don't know if that would actually give me piece of mind that a sticker and the caulking will hold the sink.

Just confirmed with my counter fabricator that a) they don't mount sinks. :) and b) they WILL be use plywood...which means, I can mount the sink, with temporary support, using caulking, and then some other suspension system - like the Hercules Sink Harness attached to the plywood to suspend the sink. At least that's what I'm thinking...

Here is a link that might be useful: Hercules harness