This problem can be seen in Optigo Spectra systems. The Optigo ONS-CX-SFP, which is used to connect Edge Switches to fiber, has a quirk in it regarding the expiration of MAC address table entries. The consequence of this quirk is that for 5 minutes after unplugging a device from the original switch, traffic from that device will not go outside of the new switch it is plugged into. This is best illustrated by images.
In this first image, the laptop is connected to the switch on the left. Any broadcast traffic it sends out, e.g. ARP, will be seen by every other ONS-CX-SFP on the system. For the SFP on the left, it sees the laptop on its copper side and saves the laptop MAC address in the copper side address table for that side. The SFP on the right along with all other SFPs on the system sees the laptop on its optical side and saves the laptop MAC address in the optical side address table.
If the laptop is then moved to the switch on the right, then the ONS-CX-SFP on the right will block any traffic leaving the switch. This is because until the laptop MAC address expires from the optical side after 5 minutes, the SFP will drop any traffic coming from the laptop on its copper side.
After 5 minutes, the MAC address table entry for the laptop on the ONS-CX-SFP will expire and traffic will resume normally because the SFPs are now allowed to re-learn the correct location of the laptop.
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