tracking is when they take the live action plates that have been filmed and they create the maya cameras that mimick what was filmed. There's also body tracking which is where we need to place geometry that is animated to follow an actor. Say for example we wanted to add wings to a character we need to body track some geo in there so we can place the wings "behind" the live action actor (without rotoscoping).
render support is exactly what it says on the tin, it's making sure the renders go through on the farm. It's shift work and it's not an easy job. Good for techy people and people that want to get shouted at a lot these guys do a thankless task but they're essential to the productions.
The average length of time in these positions is 9months to a year generally
A
Technical Director - Framestore
Currently working on: Your Highness
IMDB