Welcome to Cisco Support Community. We would love to have your feedback.
For an introduction to the new site, click here. And see here for current known issues.
Just a quick question:
How do I set the VTP domain on a 5508 WLC? Or is this even necessary (I assume it would be in order to negotiate the VLANs with the directly connected switch).
WLCs do not participate in VTP or STP (and if you are using portchannel/link aggregation they do not negotiate lacp or pagp, so you have to set the channel-group mode to "on").
So you will want to set the switchport(s) that are connected to the WLC in trunk mode, and also specify the necessary vlans in the allowed list.