Continuing from my last post on PowerMax File, I’m going to cover how to replicate an NFS filesystem from one PowerMax to another.
So let’s move now to protect our FS by setting up replication. There is also the option to use snapshots for protection, but I’m going to cover the new replication capability that utilizes SRDF. In order to use replication between two arrays, you will need to follow the steps in my first post for both arrays, save for the filesystem The FS need only exist on one array. It is unnecessary to create a FS on the second array because we are protecting the file system on the first array.
Start by selecting the Protect File System option in the banner which will lead you to the REPLICATION tab. Select Create.
Enter in a name and use the drop-down box to choose the configured Subnet. In my case with only two nodes I use the radio buttons and select Next.
You will need three open IP addresses for the network. Remember this is all on my private switch. Enter in the details and select Next.
Review the summary and select Run Now.
The new File Control Network is below.
Since replication requires two arrays, you will need to create a File Control Network on the other array. In order to do so you’ll also need to first configure a NAS server. If you choose not to create a file system on the remote array, you won’t be able to select the Protect File System option in the screenshot above, and thus get to the REPLICATION tab; however you can navigate there by selecting the NAS server, then choosing the DATA PROTECTION table as in the screenshot below. From this screen select the highlighted hyperlink.
The hyperlink will bring you to the REMOTE CONNECTION screen and from here just choose the FILE CONTROL NETWORK tab.
So development smartly added a link in Unisphere for File Protection under the Data Protection category to avoid the gymnastics I showed above:
To create the File Control Network I followed the same process so I am just showing the summary below.
With the two networks created, setup a REMOTE CONNECTION between the arrays.
Select Create in the REMOTE CONNECTION tab. Enter in a name for the connection, the cluster IP address of the remote array, and select the File Control Network. Then Run Now.
Now go to the remote array and do the same.
Replication sessions are created from the local array to the remote array. Unlike the FILE CONTROL NETWORK or the REMOTE CONNECTION, REPLICATION SESSIONS are only uni-directional. Select Create in the screen.
Fill in the appropriate information in the fields. For the destination NAS Server you are not supplying the NAS Server you created earlier, rather you must supply a new name as this will be a new NAS Server specifically for failover. The mode may be synchronous or asynchronous.
Replication sessions will only take a single primary and backup director:port even if more are configured for RDF. You also won’t be able to add more after because you can’t manipulate the group.
Review the summary and Run In The Background.
After creation note that the Health of the session might be set to a warning. Yours may be fine, mine was not which might be because of my lab setup.
If you review the alerts you will find this error:
The warning appears because the remote NAS Server the session created needs to be updated with the subnet. Navigate to the remote array, and select the hyperlink for the remote NAS Server.
Next, select the NETWORK tab, highlight the network and choose Modify.
Use the drop-down to select the proper subnet and then fill-in the radio buttons.
The result is below. Notice that the Network Device column is now populated.
After the subnet is fixed, the warning will go away and Health will turn green.
Although the replication session will show up in the SRDF Groups, much like VASA groups can only be changed in the vVol dashboard, File groups can only be manipulated in the File Configuration screen in Unisphere. In particular, you can’t add more RDF ports as I mentioned above.
Now the filesystem is protected and can be failed over to the remote array in the event of a failure to the primary array, but that’s for another post…