Since ONTAP 9.0 the recommendation has been:
“Recommend migrating 7-Mode source and destination volumes to non-SVM-DR SVM’s and then creating the SVM-DR relationship post cutover. The idea being that we avoid a re-baseline and can maintain continuity of DR throughout the migration.”
The steps used to transition existing DR relationships to an SVM-DR relationship are as follows:
(1) We start with volumes being asynchronously snapmirrored from source to destination.
Note: If you have a vFiler DR configuration, this must be deleted since 7MTT does not support this (you will need to re-create the volume snapmirrors but no re-baseline is involved).
(2) Create a 7MTT secondary transition project that will coordinate snapmirror of volumes from DR 7-Mode to DR ONTAP.
(3) Create a 7MTT primary transition project that will coordinate snapmirror of volumes from Production 7-Mode to Production ONTAP
(4) Cutover DR and then production with 7MTT, 7MTT will re-establish snapmirrors from Production ONTAP to DR ONTAP.
(5) Once cutover, you can create an SVM-DR relationship.
Note: If you want to avoid re-copies over the network, you need to cut over all the required volumes in one go, since once the you have an SVM-DR relationship you cannot 7 to C snapmirror to the disaster recovery SVM.
The simple diagram below illustrates steps 1 to 4.
Image: Transition 7-Mode DR relationships to ONTAP DR relationships
How to Convert to SVM-DR
3 points to mention prior to doing the convert to SVM-DR:
- All volumes (except svm root) must be replicated
- All volumes must have same name in the source SVM and DR SVM (including svm_root)
- There will be one schedule for the SVM-DR relationship
Before creating the SVM-DR, need to decide on using ‘-identity-preserve true’ or not.
Once converted to SVM-DR, you can have some unmirrored volumes using the -vserver-dr-protection unprotected flag.
Converting volume replication relationships to an SVM replication relationship
Replicating SVM configurations
KB article to be aware of:
Converting volume-based SnapMirror to SVM-DR relationship fails with error: Could not determine whether msid needs to be preserved or not. Reason: Root volumes do not match