Help needed with project - 2nd router with monitoring and reporting added to ISP home network?

Hi! I'm kind of a networking dummy, but I have a (hopefully) simple project I'm trying to do, and wondering if you can point me the right way?

The overall goal is "network monitoring", but with some specific caveats. The end user will connect a 2nd router to their existing gateway (which, in 95%+ of cases, would mean a standard consumer modem+router+AP like comcast/verizon gives you) with an ethernet cable. Then my router would represent a "different network" in a shallow sense - the specifics of subnets or segregation don't really matter to me.

The "Why?" here is this: the user might have family or roommates who shouldn't be affected by this additional router. The user will not necessarily be tech-savvy, so I want to minimize any changes to their basic ISP gateway setup. But for this one user in the home, I want them to switch devices to the 2nd router (move ethernet cables or switch wifi SSID), so that we can monitor their usage. Even simpler than parental controls, it just needs to watch the devices and servers they connect to (specifically, I'm interested in connections to things like gaming services and social media), log data of interest, and periodically report that to my AWS endpoint.

So I'm about to install OpenWrt on a TP-Link Archer A7 v5, which seems to be a decent enough router for this. Oh also, if this ends up limiting the max bandwidth on the 2nd router/network, compared to what the ISP gateway provides, I'm not concerned with that at this "proof-of-concept" stage. My hope is to set it up so that it broadcasts a new second wifi network, monitors traffic, and when certain domains are accessed, update a temp file, then run a cron job every minute or so to send the data in that temp file to my known AWS endpoint.

Does this all seem doable? Could you point me towards the packages / settings I need to focus on? I'm struggling to find the likely obvious answers because I'm not sure the correct terminology to use. Thanks for any help here.

Successfully got the router set up with OpenWrt. Attached the wan to my comcast router's lan, and internet seems to come through ok. For monitoring I installed darkstat and am beginning to try to understand the results visually. But I can't seem to figure out the right way to take that data and send it out. It looks like I could try enabling export and import logs, but that also seems like it would require shutting down and restarting darkstat? I'm not sure if one of the other monitoring tools would be better for this. Suggestions would be appreciated

There are quite a few bandwidth monitoring tools available, some may be able to automatically export to a database or remote server

Thanks for the link, didn't see this page yet. Looked thru the packages and still not sure which I should be using. One thing confusing me is how I would get actual domain names, eg. if I look at the network requests in my browser (like with firefox debugging tool) it'll show the url I type and the IP. I can find the IP in my darkstat hosts chart, but the host is either completely different ( becomes or just blank. Plus, I haven't been able to get this data into an export file. The darkstat page says these aren't supported below version 18.06 but maybe just not at all. I can wget the html page as an awful workaround, but clearly I'm just fumbling around making things difficult for myself.

Trying tcpdump now, but that makes even less sense to me. Maybe instead of monitoring packets I need to find a way to monitor DNS requests or something? Maybe I need to just learn more about networking in general :stuck_out_tongue: