Following the dissolution of the USSR, how were military units allocated to the newly sovereign republics?

by dragodon64

Specifically, I was wondering to what extent people recruited in republic A and stationed in republic B had a choice in returning to their homeland, getting a new citizenship at their station, or picking a different republic C.

CertifiableX

Follow up question: how was the nuclear arsenal allocated? You don’t just drop by and pick up ICBMs.