You plan looks fine. A couple of comments below.
zhang_johnson wrote:7.Import the copied backup files into the new Veeam backup server.
Instead of import, you should perform a repository rescan. Backups will be imported and you will be able to use them for replica seeding.
zhang_johnson wrote:9.failover the replication jobs.
Consider using planned failover
procedure to avoid any data loss during migration.
zhang_johnson wrote:1. Will the license be OK? coz the new veeam backup server 8.0 and the current Veeam backup 6.5 will be running simultaneously, and they will be using the same license(different versions of course).
This should be ok.
zhang_johnson wrote:2. Is that OK to connect one vCenter server to two different Veeam backup servers, and they are different versions.
No issues with that.
zhang_johnson wrote:3. Can the new Veeam 8.0 backup server import the backup files copied from the Veeam 6.5 backup repository?
zhang_johnson wrote:4. Does Veeam support replication VMs from vSphere 4.1 to vSphere 5.5? all VMs are version 7 and have no RDM disks.
Yes, such replication is fully supported.