Is this network setup Possible?

[dwijip]

Hello peeps

I am looking to purchase a ASUSTOR LOCKERSTOR 10 (AS6510T) to setup an Air-Gapped (no internet) LAN network.
The reason for this network to be air-gapped is that this setup will be in our company office which already has an WAN -> LAN network and that network is old and slow.
Also there are security issues with connecting the NAS to the existing network and the whole process will need to involve security experts etc which I really don't want to deal with.

My idea is that I purchase a ASUSTOR LOCKERSTOR 10 (AS6510T), have 2 PCs with 10Gbe adaptors and plug directly into the NAS.
Then have a normal gigabit cable run to a wireless router from which laptops can plug into the LAN or connect over wifi.

Proposed network diagram
https://drive.google.com/file/d/1EpRtd2_ctbybiEmShp52x8FWyP0AEWM8/view?usp=sharing

The sacrifice here is that this LAN with the NAS will not have access to the internet. A sacrifice for my sanity and speed/security on the new NAS network.
While I think this should work in theory I am a noob when it comes to networking and I am sure I must have missed something here.
Is there anything I should be worried about in this set up?

Any help in this matter will be greatly appreciated. Thank you

[orion]

Theoretically, yes, but only if you know network configuration well.
You can configure 3 network interfaces on NAS with different LANs (it's better to setup manual IP addresses and masks). Your 2 PCs should setup to manual IP with the specific LAN. You should keep gateway settings on NAS blank. And your router should be in another LAN (the same as NAS gigabit network interface).

[dwijip]

Theoretically, yes, but only if you know network configuration well.
You can configure 3 network interfaces on NAS with different LANs (it's better to setup manual IP addresses and masks). Your 2 PCs should setup to manual IP with the specific LAN. You should keep gateway settings on NAS blank. And your router should be in another LAN (the same as NAS gigabit network interface).

Thank you Orion
I understand that the direct link to NAS has to be configured with a static IP
but the router should be pretty much plug and play right?

Thank you for taking the time to comment

[orion]

Yes and no. If you configure gigabit LAN being the same as one of LANs of 10GbE, you should get troubles. For example, 10G LAN1 192.168.0.xxx, 10G LAN2 192.168.1.xxx, 1G LAN 192.168.0.xxx.
And, if you setup gateway as normal home gateway within DHCP server, your NAS might be able to reach internet.