Please do not upgrade to 6.0 as this particular version is nearing the end of its supported life.
I would recommend that you upgrade to the latest version, 6.2.
Please refer to the Migration Guide and Best Practice guides for details on best practices for migrations.
What are the recommendation considering EEPC 6.2 ? how many machine can be upgrade at once ? how many machine can EPO server handel ? what is recommedantion