I have now had two Cisco SG-series switches (partially) fail with the same symptoms.
The left-hand side of the ports dont work.
When the switch boots, they flash on and off as per the normal boot process, but once booting is finished, they don't pass or switch any data. The lights status lights don't change when you connect ethernet cables.
Strangely, in the web interface, it shows ALL the (nonfunctional) ports as being connected (even though they are empty).
I've updated to the latest boot code and firmware. I've done several factory resets. The right-hand cluster of ports works just fine.
To be clear, when I say the left-hand cluster of ports, I mean:
On the SG500-52P, ports 1 - 12, and ports 25 - 36 are not working
On the SG300-28P, ports 1 - 6, and ports 13 - 18 are not working
I have many dozens of SG-class switches in service, of various models. When it happened to just one switch, I thought it was just a random fluke. But now that I have experienced the same symptom on two switches, I'm thinking it might be a known problem or flaw.
Furthermore, I'm hoping that if it is a common enough problem, that it has some known solution. It seems to me that it is most likely a hardware issue (since the same group of physically related ports is "dying"). I'm hoping there might be some fix.
