I recently added a pfSense box to my network and assigned some static IP addresses. I see in my pfSense logs a ton of entries like this:

arp: xx:xx:xx:xx:xx:xx attempts to modify permanent entry for 192.168.y.yyy on igb1

It looks like something is changing my Unraid MAC address to the address represented by xxx's above. I thought maybe it was my pihole docker, but I deleted that since I no longer need it. Upon each reboot I get a different random and unique MAC address for Unraid. 

 

Any ideas what could be causing this?

11 hours ago, johnsanc said:

Upon each reboot I get a different random and unique MAC address for Unraid

Very unlikely. The MAC address of your Unraid systeem is tight to the NIC and doesn't change.

 

Seems more a configuration issue on pfsense, it receives a different MAC address associated with the IP address as configured.

 

Hmmm... I'm going to have to dig deeper into my dockers. When the Docker service is disabled, I can clear the ARP table and I get the correct MAC address. If I I start the docker service, clear the ARP table again, then I get the weird random MAC address.

 

EDIT: Ok the MAC address I am seeing in pfSense when I turn on the Docker service is the one from "shim-br0". I assume this is because I have "Host access to custom networks" enabled in my Docker settings. I believe I only needed this for Pi-Hole, but now I replaced that with pfBlockerNG. Once I disabled the custom networks I saw my correct MAC address in pfsense.

Edited June 18, 20206 yr by johnsanc

3 hours ago, johnsanc said:

I believe I only needed this for Pi-Hole

Host access is not needed for Pi-hole. It is recommended to set regular DNS servers for Unraid itself, because Pi-hole will interfere with the operation of Unraid.

 

When host access is enabled and shim networks are used, your pfSense box will see the same IP address twice and gets confused.

I believe this is a device issue. I had this issue a couple of years back and it was a security camera. I found a fix for it, but now I can't recall what it was. I have a new camera and now it is doing the same thing. If I can figure out what I did, I'll report back.

I get this from a 2 port NIC that tries to swap MAC addresses between port 1 and 2.  Check of the MAC is the same except for the last octal.  I think it is safe to ignore but I'm looking for a way to get it to stop clogging up my logs.

On 6/17/2020 at 1:24 AM, bonienl said:

Very unlikely. The MAC address of your Unraid systeem is tight to the NIC and doesn't change.

 

Seems more a configuration issue on pfsense, it receives a different MAC address associated with the IP address as configured.

 

Since about Sept 2022 every time I reboot my Unraid server my Plex docker get's a new MAC Address and is not allowed on my network until I log in and manually allow it. Seems plausible this is Unraid and not pfsense.

I also am getting random MAC addresses leaking to the broader network. I have 2 NIC's, 1 for management and the other for Docker (MAC VLAN errors...). This only seems to popup when I make a change within docker. I'll try disabling Host access to custom networks because I don't really need that enabled anyways because the router is taking care of segmentation via VLAN.