Upstream switch: Netgear GS324TP S350 v1.0.0.43 (latest release)
Downstream switch: CBS250-8PP-D v3.2.0.94 (latest release)
- PoE is disabled on both switches (only enabled for the WAP ports on the Netgear)
- Both switches set for auto-negotiate
- All patch cables used for testing passed a wave test on my Fluke to Cat-6a
- Power is via online /double-conversion UPS for both switches
- "Wall Power" to each UPS is verified steady at 120 VAC 60Hz by Fluke and Klein meters
- S350 and CBS250 have been configured to log to a syslog server
- Horizontal (in-wall) cable is STP Cat-6a installed and tested by a BICSI certified technician /company
On initial install, the CBS250 went down "hard" as soon as the upstream port was plugged in with no logged errors by the S350.
I brought the switch back to my build bench for testing and found:
Whenever I connect from the S350 to the CBS250 using a shielded cable, the switch crashes and stays crashed.
- No logs are sent when the CBS250 crashes by either device. It's as if I disconnected power - no dying gasp or other diagnostic data.
- The CBS250 crashed with both the "out of box" 3.1.1.7 firmware and after upgrade to 3.2.0.84 firmware
Whenever I connect from the S350 to the CBS250 using an unshielded cable, the switch boots and runs as expected.
I have tried shielded cables from 1m to 25m with the same crash-and-stay-crashed behavior.
I have tried unshielded cables from 1m to 15m with the same "runs just fine, no problems here" behavior.
When I connect to compute equipment (PC, Printer, IP Camera, etc.), the switch runs as expected with the same shielded cables that cause a crash when running switch-to-switch.
This happens with every port on the CBS250 and with Smartport enabled, disabled, or "hard set" for "Switch".
Any suggestions (other than running new UTP cable throughout my environment)?
