I am having an issue where I have been deploying the agent 11.2 from 11.1 for several months and I have the following issues:

There are some machines that have already had the 11.2 agent prior to system update, the console it shows up as update has been assigned even though it's at the appropriate deployed version and should be completed.
There are some machines that do not have the 11.2 agent and it has not deployed to that machine at all.
In this particular case I suspect that some machines are no longer in service. I have marked the machine to ignore the deployment but there is no change in ignoring the particular machine to ultimately get the update to the baseline state.

I was wondering the following:
What are my options to ignore the machines that have not been recognized as updated so I can baseline the update?
When a machine is no longer connected to the network and has been retired should I delete the machine from the zone or retire with the understanding it will never connect to the zone again?
Is refreshing the best option to get the 11.2 agent to a machine that has not been updated yet or should the machine be unregistered then registered again for the agent to properly automatically deploy?