Dell Unity™ Family VNX® Series Data Import to Unity All Flash or Hybrid, or UnityVSA™ System User Guide

NFS-only VDM import cutover

Before you run the cut over operation, ensure the following:

• The source VDM has not been deleted or renamed before cutover.
• The file system that is mounted on the source VDM has not been renamed, unmounted, or deleted.
• The source VDM interface has not been deleted or renamed.
• When migrating a VNX VDM that is using NIS, ensure that NIS connectivity is enabled before cutover.
  CAUTION: The Unity system firewall can block a NAS server from connecting to a NIS server. It is highly recommended to enable NIS connectivity before cutover. If NIS is not enabled after cutover, a host application may not be able to access the NAS server successfully. In this case, follow the instructions to resolve the access issue.

To resolve the NAS server access issue due to disabled NIS connectivity, enable NIS. The following example demonstrates how to do this:

1. Query NAS server with ID nas_6: # uemcli -d localhost -sslPolicy accept -noheader -u admin -p adminpassword /import/session/nas show

   1:    ID              = import_1
         Type            = CIFS
         Name            = import_sess_vdm1_APM00151909181_FNM00153800463
         Health state    = OK (5)
         State           = Completed
         Progress        =
         Source system   = RS_65538
         Source resource = vdm1
         Target resource = nas_6
         CIFS local user = cifsuser
   

2. Query NAS server network interface, for example, if_14: # uemcli -d localhost -sslPolicy accept -noheader -u admin -p adminpassword /net/nas/server -id nas_6 show

   1:    ID                            = nas_6
         Name                          = vdm1
         NetBIOS name                  =
         SP                            = spb
         Storage pool                  = pool_1
         Tenant                        =
         Interface                     = if_14
         NFS enabled                   = yes
         NFSv4 enabled                 = no
         CIFS enabled                  = no
         Multiprotocol sharing enabled = no
         Unix directory service        = localThenNis
         Health state                  = OK (5)
   

3. Query the network interface related to the port, for example, eth2 and VLAN 404: # uemcli -d localhost -sslPolicy accept -noheader -u admin -p adminpassword /net/if -id if_14 show

   1:    ID               = if_14
         Type             = file
         NAS server       = nas_6
         Port             = spb_eth2
         VLAN ID          = 404
         IP address       = 10.109.104.133
   

4. Add firewall rule for NIS server connection.
   • Example for VLAN-enable NAS server network interface: svc_firewall -udp -add eth2.404 10.109.177.170 and svc_firewall -udp -add eth2.404 10.109.177.169
   • Example for VLAN-disabled NAS server network interface: svc_firewall -udp -add eth10 1.2.3.4

When the initial copy has completed, the file import session enters the Ready to Cutover state. You can switch the production VDM from source to target so that the target side NAS server becomes the production side with all data synchronized. The cutover should be transparent to the users. After cutover, the NFS host clients can access the new production side without requiring a remount.

You can launch cutover from either Unisphere, UEMCLI, or REST. Cutover starts a job, which does the following:

1. A pre-cutover validation check.
2. Freeze the source network lock files for import. The job tries to get all the NLM data from the source VDM and import it to the target system.
3. Freeze the source file systems (frozen file systems ignore NFS request, NFSv3 lock request, and denies NLM lock).
4. Turn down the source client interface or interfaces (public IP interface).
5. Unfreeze source file systems.
6. Turn up the target interface or interfaces (public IP interface).
7. Reclaim network lock files in the target system. The job tries to revive all imported lock files in the target system.
8. Start an incremental copy.