cluster restore lost half vbucket when do cluster restore from another cluster

Install couchbase server 1.8.0 on 2 node centos 5.8 64 bit (126 and 127)
Create cluster and load 17 million items to default bucket of this cluster.
After finish loading, do stop persistent on one node and copy its database.
Do the same thing for other node
Create another 2 nodes cluster (49 and 50 with same 1.8.0 version)
Copy data base to new cluster.
Start couchbase sever and create default bucket.
Items loading correct 17 million items but when look at active vbucket, Iee only 512 vbucket in node 50.
Look at log page, see error
"Partially recovered vbucket map from data files for bucket: "default". Missing vbuckets count: 512 and HasDuplicates is: false"