That's what it is. I wasn't clear on how to set up the new IP's at Network Solutions. It wants you to set one for www, one for @ and one for *. I did that for both IP's for my VPS, but it appears the secondary was causing an issue with 404's. xue-ent.net is my domain. I'm using my VPS for private back-end data storage and retrieval, so it's not used or accessed by public.
By the way, if anyone has any information on how to set up IP "A" records properly at Network Solutions for both IP's I'd appreciate it. It has three defaults (www, *, @) for primary, so I did the same for secondary IP and that's where I ran into trouble, I think. I can't find any comprehensive help on the subject as it pertains specifically to how Network Solutions website configuration is designed.