Two homes with two NAS. Can I duplicate my iTunes library so I can listen with Sonos at both homes?

Have you tried other ways of playing the media? (Streaming the library on a computer when it is accessed as a network share, off the media playing software available on your NAS) If you ripped 1500 CDs that you own with iTunes, I don't think the files are DRM'd. If you're able to play the files through other means, it may mean that the media library wasn't properly indexed or you haven't enabled privileges to specific devices on your network.

For me, I also stream Sonos from a NAS. I had to enable user credentials with proper privileges as well as index all of my media files prior to integrating the network share into Sonos as part of my media library.

Did you clone the drives as well as the settings on your main NAS? If you have several user accounts on your NAS, some may not have access to all folder privileges and might explain why you're unable to access the files directly through Sonos.

Also, when you mentioned that "Sonos refuses to play the music saying that I don't have permission to access these files," does that imply that you were able to successfully add the network share into your Sonos music library or are you unable to add the share because your username and password aren't granting you access when attempting to add media to the library? Depending on where you are with this step, we can probably visit various scenarios to determine the cause of your issue.

Thank you for your quick reply.
I set up the same file heiarchy on the copy as the original NAS.
I simply copied the files from one NAS to the other.
I am able to play the songs that reside on the copied drive from my laptop on the network.
Please explain how to enable user credentials with proper privileges as well as index all of my media files.
I am here now at the main residence in the US with both the original NAS and portable copy until Thursday 12-29-16.
Then I leave for the vacation house with the portable NAS in Jamaica for the next 4 months.
I really need to get this working soon.

Oh, I forgot to add that I am able to tell Sonos where the files reside on the NAS. It is able to see the artist and track info. But when I attempt to play a song, it sends an error that I don't have permission.

Well, for starters, the brand of the NAS will determine where we begin. Most NAS brands have a generic way of setting up privileges dedicated for each user and its corresponding folder/network share access. In theory, if you used the same login credentials to add the network share (folder on your NAS) containing all of your media on your computer as well as your Sonos library, you should be able to access the media fine.

File indexing is conducted periodically by your NAS when you create folders for files you store on the drive. Once the files are properly indexed so that the NAS knows where everything is and can display it on another interface, your next task is to assign privileges to a user or group of users folder access. By default, all folders are generally accessible to every user unless you manually specified otherwise.

Because the files are stored directly on a NAS and not on a computer dedicated to serving your media, it wouldn't seem like a firewall issue.

Oh! I thought of something that might work, I had a friend that chanced upon a scenario similar to yours. Have you tried completely resetting your Sonos network at the new house and setting it up from scratch. It's possible that because you copied an entire library over, your Sonos system thinks it is still in the main residence when in fact it is sitting at the vacation home in a brand new environment, and so, is having playback issues.

Something else that I would explore is whether or not your NAS is on a static IP and using that as a way of mapping the share through Sonos

For me, it would be something like this when I add the NAS as a network share on Sonos.

Add media to library

--> Folder is on a network drive

\\192.168.1.x\Music

x being the latter part of the static IP of your choosing, I generally pick a number outside of the DHCP range so that it isn't confused with other devices

Username: ****
Password: ****

And Sonos should in theory find all your files and you should have no problem playing your media.

The interesting part is that Sonos was able to successfully recognize and index your media but fail to deliver on playback.

I just noticed now that you mentioned you have a RAID setup for your NAS, did you directly clone the data with the manufacturer's software over to new drives or use another method manually? I am going to assume that the two NAS's are identical, if they're not, it could explain why you're having issues with playback.

I am no expert on NASs, but i did run Sonos as two separate households on Sonos with different brands of NAS, without doing anyrhing special. Just put some music files on a NAS, shared the folder, and told Sonos that was the music library and away we went.

I would be very wary of a complete system new set up to resolve such an issue. Bear in mind that this would delete playlists, favourites, etc.

Are these Sonos playlists or iTunes playlists, if they're the latter, they're tied to the device that is streaming