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SAN COPY VNX5400 to UNITY500
I will be migrating from VNX to Unity using SAN Copy. However, there is no where in the document that really let's me know if I will experience downtime after the migration is complete. Can anyone let me know if and when I will experience downtime? If so, then how long?
Helpful answers will be appreciated.
SteveK821
2 Intern
2 Intern
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137 Posts
1
April 30th, 2018 05:00
Hello,
yes there will be a small downtime for each host for the cutover phase. Shut down the host, perform the last delta-copy in SAN copy, then remove host access for the LUNs on the VNX and add host access on the LUNs on the Unity. Then bring the host back up.
This document has a detailed description:
https://support.emc.com/docu71320_Migrating-to-Dell-EMC-Unity-with-SAN-Copy.pdf?language=en_US
I have done this for a few migrations and it is fairly easy. For Windows hosts I had to manually bring the disks online in disk manager, but they were recognised with the correct drive letter straight away. There is also an import assistant which can automate this process, but it also requires a downtime for the cutover.
Regards,
Stephen
miwoods1
4 Posts
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April 30th, 2018 10:00
Thank you,
Do you know if it will take minutes to hours for the cutover/downtime? We already have some of the Hosts connected to the Unity. So when we migrate the LUNs over to it, then we shouldn't need to bring the hosts that are already over there down correct?
SteveK821
2 Intern
2 Intern
•
137 Posts
1
May 2nd, 2018 00:00
No, if they are connected to the Unity it only means that you won't have to do additional zoning. It should only take minutes.
For the cutover, you need to take the VNX devices offline for the host (unmount them in the OS or shutdown the host).
Then perform the last incremental copy in SAN copy so that the LUN content on VNX and Unity are identical. If you perform incremental copies regularly before the cutover, there should not be much more data to copy. Then delete the SAN copy session(s) for that host, remove the host from the host group on the VNX. On the Unity, remove access for the target LUNs for the "VNX SAN Copy Host" and add Host access for the Host. Your host should not be allowed to see the target devices until SAN copy has been completed and the source devices are no longer visible for that host.