Network performance degradation.
Low transmit (Tx) power levels on 32G SWL optics.
Products that may experience this issue:
- DELL EMC Hardware: Connectrix DS-6610B
- DELL EMC Hardware: Connectrix DS-6620B
- DELL EMC Hardware: Connectrix DS-6630B
- DELL EMC Hardware: Connectrix ED-DCX6-4B
- DELL EMC Hardware: Connectrix ED-DCX6-8B
- Brocade Labelled 32GB SHORT WAVE SFP
Brocade part numbers:
- XBR-000212, SFP+, SWL, 32G, 1-PK
- XBR-000213, SFP+, SWL, 32G, 8-PK
Issue:
Broadcom has seen instances where network performance degradation is seen. Isolation to the source of the network degradation has shown it to be a result of low transmit (Tx) power levels in 32G SWL optics on the switch.
32G SWL optics experiencing transmit level (Tx) issues may cause CRC, ITW, or Bit errors to be logged at the device port attached to the optic in question. These errors may result in a loss of buffer to buffer credits, which may lead to link resets across that link. Any of these issues may cause performance problems across the link and throughout the fabric.
For severe signal degradation on the Tx port, attached devices may experience log in or connectivity issues.
On a global basis over the entire install base, Broadcom is seeing an expected small rate of failure, (<0.3%). Certain lots of chips that come from specific wafers have shown a failure rate that is beyond our normal standards. Because of the nature shipments from lots, it is possible to be exposed to the higher failure rate.
Broadcom and their supplier are committed to addressing the situation. SFPs will be replaced upon failure or degraded/low Tx power outside of threshold.
Broadcom s supplier has isolated an issue of weak oxide layer with data correlating to higher failure rates on specific wafers. The supplier has isolated a set of tests executed on failed components that uniquely identify the signature of this fault.
Other instances come from typical optic faults, but due to differences in transceiver laser drivers and error reporting, some of the self-reporting features of the optic for low transmit levels are not present which has added a level of difficulty to the troubleshooting process.
Brocade TSB 2019-274-A
Fix: Automated monitoring for optics was added in Fabric OS 8.1.2f and 8.2.1 and later.
Note: Requests for this TSB event will NO longer be accepted. (Expired 1st July 2020). Any Optic claim requests will be subject to normal customer support and warranty terms.
Brocade TSB 2019-274-A