Techniques are presented for implementing non-host-based migration in a manner that is not subject to certain types of data corruption. This may be accomplished by preventing any hosts from having write access to a target LUN until it can be confirmed that all applications that access a source LUN have been shut down. This arrangement prevents accidentally writing to the target LUN while the source LUN is still being accessed. As a further precaution, just in case the confirmations are incorrect, a target data storage system can direct a source data storage system to remove access to the source LUN from all of the hosts, which has a similar effect. The migration can then proceed.