case packer rack went down around 1am, 1756 en2t in slot 3, OK led solid red. grabbed the spare en2t out of the crib, switches on it were 999 same as the dead one, dropped it in. it came up, scrolled an address, then the NET led went solid red and stayed there.
about a minute later line 2 rang, their palletizer rack is down as well, same solid red NET led, and line 2 is on its own switch in its own panel. i tried a different port and reseated the spare twice, no change.
is the spare bad too? not sure what to make of line 2 going over at the same minute. we have one more spare but im not putting it in until someone tells me why, any help would be appreciated
Solid red NET on an EN2T is duplicate IP detected. The module shuts its own port. It doesn't need a switch to do that.
What address does the spare scroll on the display, and what does the line 2 module scroll?
spare scrolls 192.168.10.41 then a line about duplicate and a mac, cant read it in time. line 2 guy says his palletizer en2t scrolls the same thing, 192.168.10.41 and duplicate. ours is supposed to be .23, thats what the dead one had.
so both of them think they are .41? line 2 has its own switch though.
Own switch isn't own network. If both panel switches uplink to the same core on one VLAN then it's one flat layer 2 domain, and a duplicate address is seen everywhere on it.
What happens is the spare comes up, sends an ARP probe for 192.168.10.41, the line 2 module answers, and both of them detect the conflict and shut their ports. That's the address conflict detection in the EN2T doing what it should. Wireshark on either panel would show the probe and the reply, one line each.