OpnSense hangs LAN after restart- No access in LAN for devices

[Pipe]

This Post is a copy of my post in Portuguese. Reason: No answers there. So now I'm looking for help here. Here is the link to the original post:https://forum.opnsense.org/index.php?topic=45964.0

Trouble:

Let's say a bizarre problem... I'll try not to go into too much detail.

Last night, out of the blue, my FIre Stick stopped, Messages on WPP weren't going out... I saw that I couldn't access the Opnsense web GUI. I restarted my Switch and it came back (which I didn't agree with). This morning I went back to it.
I lost full access to my Appliance with OpnSense installed. After restarting, even with a network cable directly to the switch, it could not be accessed. So I restarted switch and it came back again. Not satisfied, I plugged the UTP cable directly into the FW's LAN port. To my surprise, it didn't access, I restarted, it accessed..

I replaced the Firewall with a desktop that I have left here. I uploaded the Backup, adjusted the ETH's, everything was fine and working beautifully.

In the afternoon, after completing the download of the latest update (25.1), as I was still on 24.7.xx. After that, FW rebooted as expected. Guess what?? I could no longer access it. I went down to the garage and turned on the monitor and there it was, on the Pormpt Login screen, that is, normal!
What I did then:
1. I restarted SW, it worked.
2. I changed the SW (for the third time), same symptom, when I rebooted the FW, LAN access only came back after restarting the SW.
3. I changed the ETH LAN (Realtek) to the WAN (Intel PRO), in the OpnSense web interface, to see if it was something with the ETH Realtek (even though I had already installed the os-realtek driver), same symptom.
3. I connected a UTP cable from my notebook to the OpnSense LAN directly. I rebooted, and to my (not so expected surprise, as it was not possible for me to have 3 defective Switches), after uploading OpnSense, again without LAN access.

Summary Symptoms:
Every time OpnSense is restarted, LAN access is lost. Access only resumes after restarting Switch. If connected with a cable directly between the notebook and LAN, same behavior.
Symptom on client devices: No network identified.

I would appreciate it if someone could give me some light.

Thanks


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Dear,

Updating my tests.

I installed another Firewall (Hardware) with another OS. The brand here is irrelevant.

I left the same LAN/WAN settings, identical.

I put it as FW on my network, restarted it several times and the result: It worked normally.

I confess that I am very worried. Even because, I have a project with a remote client that I have already left 2 Firewalls ready with OpnSense.

[pfry]

I'd start with ARP: Check ARP caches on all machines ("arp -a" or "Interfaces: Diagnostics: ARP Table" on OPNsense) and forwarding database on the switch, and logs on firewall (for ARP movement - unlikely in this case). Not just presence, but correct MAC to IP mappings. A bit of a long shot, but a start.