Cannot find IP addresses of hosts connected to switch

I have an OpenWrt router with IP 192.168.0.1 and a network switch connected to LAN port 5. The network switch has a static IP of 192.168.0.2.

My issue is I cannot see the 3 connected devices (IP or MAC) on this switch. I can see traffic under Status > Real Time Graphs > Traffic > LAN5.

I can log into the switch's portal using a browser and see traffic on all three ports being used.

I have tried the arp and nmap commands, but it will only show me the IP and related information for the switch itself.

I have tried enabling "Accept packets with local source addresses" under Interfaces > LAN5 > Configure > Advanced Device Options, but that didn't help me see anything.

Surprisingly my old non OpenWrt router let me see all device, whether wired or wireless.

I'm looking to find these IP addresses so I can ssh into them, assign them a static IP in the OpenWrt router.

What's interesting is after the initial setup of the OpenWrt router, when it had the default 192.168.1.1 IP address, I was able to find the IPs of the hosts on the switch. They were all provided 192.168.1.x IPs and were accessible via cli and browser.

If you changed the lan IP on the Openwrt device "just now" the devices communicating via the switch won't know this, until it's time to renew the DHCP lease.

So instead of waiting for those leases to expire, I can force a renewal of the switch and all the connected devices.

Ok I found this page with steps to force a renewal. After a reboot I can now see one of the devices under Active DHCP Leases, but not the other two.

You can't force them from the Openwrt device, but they'll do it, if you reboot the switch, or temp pull the ethernet cables.

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