Rolling Upgrade from 6.1 to 7 not working

[standalone@localhost:10990 /] /subsystem=datagrid-infinispan/cache-container=clustered/replicated-cache=sample-cache:synchronize-data(migrator-name=hotrod)
{
    "outcome" => "failed",
    "failure-description" => "DGISPN0118: Failed to invoke operation: java.lang.ClassNotFoundException: org.infinispan.util.ByteArrayKey from [Module \"org.infinispan.persistence.remote:main\" from local module loader @42f30e0a (finder: local module finder @24273305 (roots: /home/gfernandes/migration-tool/jboss-datagrid-7.0.0-server/modules,/home/gfernandes/migration-tool/jboss-datagrid-7.0.0-server/modules/system/layers/base))]",
    "rolled-back" => true
}