CIFS vFiler Migration to Cluster Mode

[TMADOCTHOMAS]

I have seen some contradictory information on migrating a CIFS vFiler in 7-Mode to a CIFS Server in an SVM in Cluster Mode and would like to see if anyone can provide some clarity.

First, the basics: I have six vFilers to migrate, each going into their own SVM.  For all of them, we are preserving the identity of the vFiler - i.e. we want the name to stay the same once it is functional in Cluster Mode.  For five of the six, we want to migrate the IP address as well.  For one of them we want a new IP.

I was under the impression that in order to preserve the vFiler's identity, I had to create a temporary CIFS server on the Cluster Mode system during the 7MTT migration.  At cutover, I would terminate CIFS on the 7-mode system, tear down the CIFS server on the Cluster Mode system, and recreate it with the identity of the vFiler from the 7-Mode system.  We would then complete the migration.

However, having read tr-4336, page 61, and the 7MTT 2.0 Data and Configuration Transition Guide, page 58, it appears that I have it backwards.  These documents appear to say that, before pre-cutover, I need to terminate CIFS on the 7-mode system, tear down the vFiler on the 7-Mode system, and recreate it with a temporary name before pre-cutover.  I would then need to create the new CIFS Server on the cluster mode system using the identity of the original vFiler.

I would be interested in hearing from anyone who has performed migration of CIFS vFilers.  The main things I'm trying to determine are:

1. Do I need a temporary CIFS Server on the Cluster Mode system, or a temporary vFiler on the 7-Mode system?  Or do we need all three running at the same time - the original vFiler and a temporary vFiler AND CIFS Server?
2. If the latter, if the goal is to preserve the 7-Mode configuration information so it can be transitioned, how is that possible if I am creating a new vFiler, presumably using the same root volume as before, which wipes out the original configuration?

Any thoughts or advice will be appreciated!

[SeanHatfield]

On recent versions of ONTAP you also have the option of completing the cutover on the temp cifs ID, then modifying the vserver's cifs-server name.

[TMADOCTHOMAS]

Thanks for the tip! That's good to know as we will have several more 7MTT jobs next year as we try to upgrade our 2220's to cdot.

[DLista]

Hello guys, I'm new on migration and still learning. I don't understand how do you migrate the data previous to configure the cifs vserver on the cdot. How do you configure the vserver destination? That's not clear for me.

[TMADOCTHOMAS]

DLista, see my post at the top of this page, I think it may answer some of your questions. if not, post again.

[naga_queen]

Hello,

This is the workflow that has worked for us and we have been using this sequence to successfully transition 7-mode vFilers with CIFS volumes to clustered ONTAP.

MAINTENANCE STEPS

1. Close open files and sessions on the CIFS share.
2. Write down the CIFS share configuration and current sessions on 7-mode.
3. Gracefully terminate CIFS service on the vFiler.
Note: it is not a requirement to disconnect CIFS shares from client end. The best practice is to discontinue connectivity from storage side. However, if there will be any IP or share name/path changes, shares must be disconnected from client end as well and re-connected after cutover.
4. Assign a temporary CIFS server name on the vFiler and update DNS.
Re-run CIFS setup on the vFiler in order to reconfigure the CIFS server to use a temporary name.
Update DNS to point the IP to this temporary name. Remove the AD computer account for the original CIFS server identity. A new AD computer account with the temporary identity will be automatically created during CIFS setup.
Note: CIFS service should be running with the new temporary identity because it is required to read CIFS configurations from the vFiler during pre-cutover phase. 
5. Configure CIFS on the SVM with the original 7-mode identity ("vserver cifs modify" command for ONTAP 9.0 or later).
Create an AD computer account for the original CIFS identity and verify CIFS server is now running with this identity.
6. Apply configuration and move project to Precutover phase.
Note: Ensure that CIFS server is running on the source vFiler and the target SVM!
7. Perform cutover.
8. Update DNS and AD computer account.
Update DNS to point the CIFS IP to the original CIFS identity. Remove the temporary AD computer account which was automatically created during vFiler CIFS setup along with the temp CIFS server which was initially configured on the SVM.
9. Perform cleanup tasks.
- verify CIFS lif is up on the SVM
- remove the CIFS lif which has been initially configured on the SVM so that it could be temporarily joined to the AD domain
- verify volume is online and writable, and shares are visible
- verify CIFS export policy and rule are applied on the SVM
- verify volume is junctioned into the SVM namespace
Note: if volume was transitioned with its 7-mode path, unmount the volume from /vol directory and mount it into the SVM namespace (/).
- delete vserver peer transition relationship
- update the ls-mirrors for the SVM root volume
10. Ensure CIFS shares are accessible from client end.
Connect shares with the new path along with all prefixes (if /vol direstory has been removed). Ensure write operations are successful.

Good luck with your upcoming CIFS transitions!