I know that this is a mildly dated thread, however, I've just ran into this issue at a client site where we were making a number of modifications to SnapMirror configurations with a direct-attached to UCS setup and the fix was not to add the new NetApp VLAN to a Service Profile vNIC. The fix was to navigate to each of the appliance ports (in our case just one per fabric) and verify that the newly-created Appliance VLAN was actually checkmarked to enable it on the Applianct Ports. It did also have to be in both the Appliance Cloud and the LAN Cloud as a Global VLAN.
Thanks Chris. In my case the issue was that I didn't create the same VLAN in the LAN cloud but only created in appliance cloud. Hence it failed. Issue got resolved after creating the same VLAN in LAN cloud after referring your solution.
It's going to be hard to troubleshoot with out many details on the configuration. To start with, make sure that the VLAN you have configured on the Appliance port exsits in both the LAN Cloud and Appliance sections.