DHCP client issues - looks like hardware failure, but it talks to DHCP server

Tango

This is a follow up to another post, but this includes some different information. While it seems to be the same issue and closely related, I think this is going in a different direction.

I was having problems with a Pi 3B+ and it would not connect to my LAN. We thought it was a hardware issue, so I got a new Pi 3B+ and put the USB stick with the full OS from the old one into the new Pi. I booted it, it came up, but it wasn't connected to my ethernet cable. Then I connected and it got an IP address, but not the one I expected. That's when I realized it was a new MAC address. I took a screenshot with my phone, went across the room to my desktop and changed the setting in my DHCP server to use the new MAC address for that system. When I got back over to the Pi, it was showing only an IPV6 address, no IPV4. I was wondering if something was wrong with my ethernet cable or the switch connection, but this connection worked fine on a 3B+ until yesterday afternoon and, last night, when I had issues with the older 3B+, I turned on a server I wasn't using and connected it. The cable tested okay.

So now I'm not getting a connection, but when I use journalctl -u dhcpcd, then ifconfig, here's what I get:

Read starting at the 2nd line:

dhcpd is trying to get a lease (I don't know if it can do that without a network connection or not)
It's offered an address, the correct one (now that I've updated the DHCP server to look for the MAC address you can see for eth0: where I've run ifconfig.
Then it repeats - many times.

There are three things I think are notable here:

It's talking to the DHCP server, since it is being offered a lease, so I think the hardware is okay
It is being offered the correct address for the MAC (b8:27:eb:90:8:19)
After that, it says the hardware address 38:18:4c:33:26:2d is claiming the address - this is NOT the MAC address given for eth0:

I have no clue what's going on. I thought the "hardware address" was the MAC address. Is it?

Any ideas what I can do to troubleshoot this or fix it?

Tango

Addition:

I checked the dhcp logs for the dhcp server. (I'm using PFSense for a firewall and using the dhcp server on there.) I'm finding this line repeated in the logs regularly and frequently:

dhcpd: uid lease 172.16.7.174 for client b8:27:eb:90:88:19 is duplicate on 172.16.7/24

However, and I've checked this in case I'm having a reading issue, in the dhcp configuration, I have specified that 172.16.7.17 be assigned to that MAC address. Since I saw this and wondered if there could be a typo issue or something hincky like that, I changed the assigned address to 172.16.7.8 and I still keep getting the same message.

Also, there is no lease for 172.16.7.174 in the list of active dhcpd leases.

Tango

This has been resolved and the answer is on this thread that I referenced earlier.