- Make folder named made_before_a
- Take snapshot named a
- Make folder made_before_b
- Take snapshot named b
- Make folder made_before_c
- Take snapshot named c
- Remove all dirs and save state of machine
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Discard current snapshot and state
This option removed snapshot c and the Current State (changed).
Revert to current snapshot
After this my guest os was in a state at which snapshot c had been taken (i.e. folders made_before_a, made_before_b and made_before_c were restored)
Discard snapshot
Final option is discard snapshot.
Conclusions
- Revert to current snapshot - it moves guest os to the state it was when the snapshot was made. All changes made since the snapshot creation time will be lost.
- Discard current snapshot and state - it moves guest os to the state of the previous snapshot. Current snapshot and all changes are lost. In my example, performing operation 'discard current snapshot and state' on snapshot c, moved my systems to state of snapshot b.
- Discard snapshot- it removes a snapshot, but not the changes made since the creation of the snapshot.
Hope it will be useful and hope I did not make any mistake (apart from my English :-)).