United States joined 7 months ago
5 questions
19 comments
Optical transport specialist from Austin. Mostly MikroTik and Ubiquiti.
Building a storage box at home and picked up a dual 10GbE Solarflare SFN7122F (SFC9120) because it was cheap. The card itself looks healthy, the system sees it and both ports enumerate, but not one of my existing multimode SFP+ modules will bring up a link in it. Solarflare SFN7122F, dual port…
I picked up a couple of second-hand Arista switches for the lab and ran straight into the optics gate. Arista-coded modules link up, passive DAC cables link up, and anything third-party leaves the port down. The lab side: DCS-7150S-24, bought used, no support contract and no account team behind me…
The poster compiled and loaded i40e 3.4.2 on Ubuntu 16.04 for an Intel XL710-QDA2 dual-port 40GbE adapter. The driver loaded fine, but as soon as non-Intel QSFP+ cables were attached dmesg reported "Rx/Tx is disabled on this device because an unsupported SFP+ module type was detected." and no link…
A Cisco Nexus 5672UP fitted with a 10GBASE-SR SFP+ could not connect to another switch that uses a 1000BASE-SX (1 Gbps) transceiver; both ends are multimode optics. When the poster changed the port speed, 'show interface brief' displayed an 'SFP checksum error', and swapping the Nexus optic for a 1…
The poster needs a 100GE link between a Cisco NCS55A2-MOD (NC55-MPA-4H-S MPA) and a Cisco Catalyst C9500-48Y4C using a QSFP-100G-CU1M DAC. Both platforms list the cable as supported, yet the link never comes up at the physical level. Because the Catalyst 9500 lacks 100G auto-negotiation (bug…