Traditional:1. 建一个Diskgroup至少3块盘(每mirror plex不能在同一块盘上)
2. 在这个Diskgroup创建一个layout=mirror的Volume nmirror=2
vxassist -g datadg make datavol 100m layout=mirror,nolog nmirror=2 alloc=datadg01 datadg02
2. vxvol set fastresync=on datavol 打开fastresync
3. vxassist -g datadg snapstart datavol(为snapshot做准备，即加入一个Plex形成3个Plex的Volume
新加的Plex是在datadg中的另一块subdisk上建立的，并且与前2个Plex进行同步
4. vxassist -g datadg snapshot datavol snapvol 新加入的Plex与datavol detach并生成snapshot volume
5. vxassist -g datadg snapback snapvol snapshot还原到原来的Volume中，和snapstart时一样
6. Clear the association to create an independent volume.
vxassist -g datadg snapclear snapvol
7.Destroy PITC
vxassist -g datadg remove volume snapvol
FastResync must be enabled for a volume in order to use this command. Snapshot objects (ss) and detached plexes (dp) are used by FastResync to track associations between a volume and its snapshot volumes
Instants: 1. vxassist -g datadg make datavol 100m datadg02建立datavol卷
2. vxsnap -g datadg prepare datavol (Enable FastResync)
此时自动建立datavol_dcl卷(100MB的datavol,datavol_dcl只有227KB,datavol有几个Plex datavol_dcl就建立几个
DCO log Plex用来记录做snapshot后datavol上数据的改变,以便通过snapshot可以快速恢复
3. vxsnap -g datadg addmir datavol 为datavol添加mirror plex(同Traditonal的第3步)
4. 建立一个空Volume作为snapshot volume用 (如果建空Volume转到5,也可以不建转到6)
LEN=`vxprint -g datadg -F%len datavol`
DCONAME=`vxprint -g datadg -F%dco_name datavol`
RSZ=`vxprint -g datadg -F%regionsz $DCONAME`
vxassist -g datadg make snapvol $LEN init=active
vxsnap -g datadg prepare snapvol regionsize=$RSZ
5. vxsnap -g datadg make source=datavol/snapvol=snapvol
把datavol中的一个Plex移动到snapvol作为snapshot volume
并不把datavol里原来新加的Mirror Plex转为snapvol volume里作为Plex
而是在datadg里的另一快磁盘建立subdisk并作为snapvol的Plex
6. vxsnap -g datadg make source=datavol/newvol=snapvol/plex=datavol-01(用哪个Plex去建新的Volume)
7. 刷新snapvol与datavol同步
vxsnap -g datadg refresh snapvol source=datavol
8. 重新加入回datavol变为一个Mirror Plex
vxsnap -g datadg reattach snapvol source=datavol
9. 解除snapvol与datavol的关系,snapvol变为独立的Volume
vxsnap -g datadg dis snapvol