By default, 517 Kbytes or 1034 disk blocks of a slice. Because your disk slices may not be that small, you may want to resize a slice to hold the state database replica. (See Solstice DiskSuite 4.2.1 User's Guide for more information on resizing a slice.)
Three (3), preferably spread out across at least three disks (to avoid a single point-of-failure). DiskSuite does not operate with less than a majority.
You can create state database replicas on slices not in use.
You cannot create state database replicas on existing file systems, root (/), /usr, and swap. If necessary, you can create a new slice (provided a slice name is available) by allocating space from swap and put state database replicas on that new slice. See Solstice DiskSuite 4.2.1 User's Guide for more information.
Yes, but you must create it before adding the slice to the metadevice. You can also create a state database replica on a logging device. DiskSuite reserves the starting part of the slice for the state database replica.
In general, it is best to distribute state database replicas across slices, drives, and controllers, to avoid single points-of-failure.
If you have two disks, create two state database replicas on each disk.
The rest of your configuration should remain in operation. DiskSuite finds a good state database (as long as there are at least half + 1 valid state database replicas).
What happens when state database replicas are repaired?
When you manually repair or enable state database replicas, DiskSuite updates them with valid data.