Changing the secondary site

This topic lists the steps to follow when the secondary site stops functioning.

Complete the following steps if the secondary site stops functioning:

Create a new GPFS™ independent fileset on the new secondary site.
Copy the data on the primary site to the new GPFS fileset by using ftp or scp. This is known as outband trucking.
Run the following command to establish a new secondary site for the primary site:
```
mmafmctlDevice changeSecondary-j FilesetName    
--new-target NewAfmTarget [ --target-only |--inband | --outband ]          
[-s LocalWorkDirectory]
```
The --inband or --outband option is used depending on the method that is being used to truck data. --target-only can be used if you want to change the mount path or the IP address in the target path. The new NFS server must be in the same home cluster and must be of the same architecture as the existing NFS server in the target path. --target-only must not be used if the home is completely changed, or if you want to change the protocol while using the same home cluster. While using the same secondary path, if you want to change only the target protocol from GPFS to NFS and vice-versa, you can use mmafmctl changeSecondary command.
Convert the GPFS fileset on the new secondary site to a secondary and set the primary id by running mmchfileset or mmafmctl with convertToSecondary option.
Ensure that the NFS export on the secondary site is accessible on all the gateway nodes on the primary cluster if NFS is used for defining AFM target on the primary site. If the GPFS protocol is used for the target, the secondary file system must be mounted on all gateway nodes on the primary site.

After the primary and secondary sites are linked, the psnap0 queued from the primary fileset is played on the secondary fileset. The new secondary site is now linked to this primary site. Ensure that the primary filesystem is mounted on all gateway nodes and new secondary filesystem is mounted on all the nodes in the secondary cluster.

Using the primary fileset to make changes to the secondary fileset

Replace the secondary with a completely new empty secondary where the new target is using NFS/NSD/mapping. The administrator must run the mmafmctl changeSecondary command without --target-only option to point to the new secondary. The new secondary is expected to be empty. If the new target is a mapping, changeSecondary does not split I/Os and queues them as normal requests without parallel data transfer.
Replace any of the following on an existing secondary:
- Replace the communication protocol (NSD/NFS):
  The administrator must run the mmafmctl changeSecondary command without --target-only option, using the new target protocol.
  Note: Only the protocol changes and not the secondary path.
- Enable or disable parallel data transfer PIO by shifting between NFS/NSD and a mapping:
  The administrator must run the mmafmctl changeSecondary command without --target-only option, using the new target protocol or mapping.
  Note: Only the protocol changes and not the secondary path.
- Replace only the IP address or NFS server using the same communication protocol and secondary path:
  The administrator must run the mmafmctl changeSecondary command with the –target-only option.
  Note: Only the IP or NFS server changes. The IP/NFS server must be on the same secondary cluster and must be of the same architecture as the old NFS server.