Configuring multiple DSA Network Client instances is required when there are two different networks at a site. Sometimes a site might have two private networks, or a public network and a private network.
For example, at a site where one media server is configured with a private network and a public network, in order to run a restore job using the public network, the private network IP addresses must not be used. In this situation, create two instances of DSA Network Client so that you can create two media servers in DSC. You can configure one of the media servers with addresses belonging to the public network, and one media server with addresses belonging to the private network. When a restore job must run on the public network, the media server configured with the public address is used instead of the media server with the private address.
You can also create a target group with the public media server and another target group with the private media server. If you create a Restore group between the private target group and the public target group, you can run a restore job using the Restore group over the public network.