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This shows you the differences between two versions of the page.

--- san_migrations [2019/03/22 21:57] – [What is a SAN Migration] sgriggs
+++ san_migrations [2019/03/22 22:04] – sgriggs
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 In the above diagram you can see a migration example where the client wants to move to a new SAN and they are also going to ditch their old switches. However, since they don't want to take downtime until the old SAN and old switches are completely migrated away, they will continue to let the host talk to **both** of the SANs with an ISL link between switches. Once they are done, the client will need to physically move from the old set of SAN switches to the new set. This is usually a very quick outage just long enough to change the cables.
+==== How Does PARSEC Do Migrations? ====
+We do not rely on fiber "appliances" to do our SAN migrations. We believe that to be a mostly inferior method since it requires something to permanently spoof the old SAN. It's like it's ghost is still around and you can never forget about it. There are a lot of other problems with SAN migration appliances, too. One of the biggest issues is that they usually charge you by volume (of your data migration or of your fiber host WWPNs). So, a big company who gets a SAN appliance for a major migration will pay a lot more.
+The way we do our migrations is via our mastery of the host based tools in the operating system. We actually re-federate the storage completely from your old to new SANs. In order to this we use specific tools. Let me give you some detail for each OS we support.
+  * **OpenVMS**: we use the VMS feature known as "Volume Shadowing" in order to create mirrors of your old data onto your new SAN. When the mirroring completes, we break the relationship and you are off your old SAN forever. This usually requires zero downtime.
+  * **AIX**: We use the Logical Volume Manager (LVM) which comes with the operating system to migrate your logical volumes to new physical volumes by adding old LUNs to new LUNs in the volume group, then creating mirrors of each logical volume on the new SAN LUNs. This usually requires no downtime to migrate. We also have scripts and tools which enhance the process by giving you status, estimated time of completion, and managing multiple mirroring operations simultaneously where possible, speeding up the migration considerably.