create snapshot	snapshotof=<volName> [size=<size>[kKmMgGtT]]
        		[options=<lvCreateOptions>]
delete snapshot <snapName>|<volName>
reset snapshot  [volName] | [snapName]
rollback snapshot    [snapName]
copy snapshot    <snapName> <destVolName>|<device>
set snapshot    <snapName> [size|capacity=<size>[kKmMgGtT]]
set snapshot    <volName> interval=<none|frequent|hourly|daily|monthly> 
        		[period=integer] [keep=integer] [offset=integer]
set snapshot    <volName> [groupTag=string]
show snapshot   [<volName>|<snapName>]

mayacli create snapshot snap_test snapshotof=testvol size=20G
mayacli show snapshot
mayacli set snapshot testvol interval=daily period=3 keep=8