IHAC who is looking for the following replication scenario -
They have a prod site and a DR site both with Unity arrays. The prod site has a production NAS server with a bunch of FS and NFS shares mounted on it. They want to replicate only two of the FS to their DR site and test the data from the replicated FS on their DR servers (read only, no writes). They don't want to bring down the prod nas server, simply pause the replication for the nas server and the two concerned FS. Is this something that could be done?
From my understanding of the way the replication works, you would ideally have to failover to the DR site - but since they are replicating only 2 FS, a failover would bring down all the FS mounted on that nas server. I remember there was a way we would do this for CIFS on the older VNXs (not recommended of course), but I'm not certain about the Unity. Any ideas?
CIFS access to a destination mode (readonly target of an async replication) NAS server is currently not possible
On VNX this was done via DM global CIFS server - which doesnt exist in the Unity multi-tenancy architecture of separate NAS servers
After a failover of course the destination assumes the identity and you can access using CIFS
What you can do with the current VNX OE in order to check the replication side or restore files is:
- configure ftp/sftp and access via winscp - this way you can easily browse through all file systems and snapshots of a NAS server. since you cant authenticate using a CIFS account on the dst without a running CIFS server easiest way is to use local account via passwd file
- use ndmpcopy if you want to restore/copy data to another Unity system or NAS server - especially useful since ndmcopy copies both CIFS and NFS attributes and ACLs.
- access via NFS - but you first need to create a read-write snapshot before you can export it via NFS from the dst NAS server
Remember that in order to access the dst NAS server you also need an active interface there. The way to get one is to configure an interface of the type "backup/DR" on the src NAS server - this config will replicate to the dst NAS server and the interface will work there when the dst NAS server is in destination mode
For the next major release - currently in beta - a readonly CIFS access is planned via a new proxy NAS server functionality
yes - for each file system or snapshot you want to make available you would have to manually create a protocol (read-write) snapshot before you can NFS export it
reason is that on the DR side Unity will currently not allow you to NFS export a readonly object
scp/ftp is a seperate protocol - it uses Unix attributes but you can access CIFS data through it as well
see the VNX manuals - they explain it nicely and it mostly also applies to Unity
Rainer_EMC
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Posted December 5th, 2017 04:00
CIFS access to a destination mode (readonly target of an async replication) NAS server is currently not possible
On VNX this was done via DM global CIFS server - which doesnt exist in the Unity multi-tenancy architecture of separate NAS servers
After a failover of course the destination assumes the identity and you can access using CIFS
What you can do with the current VNX OE in order to check the replication side or restore files is:
- configure ftp/sftp and access via winscp - this way you can easily browse through all file systems and snapshots of a NAS server. since you cant authenticate using a CIFS account on the dst without a running CIFS server easiest way is to use local account via passwd file
- use ndmpcopy if you want to restore/copy data to another Unity system or NAS server - especially useful since ndmcopy copies both CIFS and NFS attributes and ACLs.
- access via NFS - but you first need to create a read-write snapshot before you can export it via NFS from the dst NAS server
Remember that in order to access the dst NAS server you also need an active interface there.
The way to get one is to configure an interface of the type "backup/DR" on the src NAS server - this config will replicate to the dst NAS server and the interface will work there when the dst NAS server is in destination mode
For the next major release - currently in beta - a readonly CIFS access is planned via a new proxy NAS server functionality