also, pick your log disk carefully
several decades ago, almost four, I had to break a disk cluster on a VMS system. this is a job to beware. but it needed to be done to advance reliability. so, since there were more users than space on any single disk, had to divide them. didn't work well to split halfway down the first letter of last names, so I had to count instances and fork them left and right. test went fine. so one night, kicked off the script.
first AM when users started logging in, they couldn't. I couldn't remotely. so I used the admin credentials.
logging went to the system disk because, space.
until there was none.
deleted the log, drove in, job done, lesson learned. should have flipped the logging over the VAXcluster to another machine. learn, grasshoppers.