Popular discussions about programming, compatibility and testing of optical transceivers.
The thread starter wanted to reprogram GBIC and SFP module EEPROMs but found that guides were disappearing from forums. Questions covered which programmer to use, where to attach the I2C lines on the module, whether the module needs 5 V (GBIC) or 3.3 V (SFP), and how to treat the memory as a…
The poster asked whether a 10G SFP+ SR or LR optic in one switch can auto-negotiate down to 1G to link over fiber with a 1G SFP in another switch, and if not, how to attach a handful of 1G optical connections from a 1G switch to a 10G switch. They understood that Cisco SFP+ optics run only at 10G…
The poster spent a day and a half chasing an Intel 82599EB-based 10G SFP+ NIC that VMware ESXi 6 reported as down although the link LEDs were green on both ends of the fibre and the Cisco 8500 switch showed the port up/up. The cause turned out to be the Cisco SFP-10G-LRM module used throughout…
The poster asked whether anyone had used third-party optics in a Cisco Catalyst 9300 series switch running IOS XE Everest (16.x), and specifically whether the hidden global command 'service unsupported-transceiver', long used on older Catalyst platforms to accept non-Cisco SFPs, still functions on…
The thread starter had a set of Cisco EEPROM images (SX, LH, ZX types) but no CWDM images and wanted CWDM SFP modules to show up on Cisco switches as CWDM/WDM optics rather than being misidentified as SX or LX. Without a correct image the switch either reported the module as unsupported or forced…
For a deployment on Dell PowerEdge R630 and C4140 servers the poster had Intel X520-SR2 adapters (E10G42BFSR) fitted with the bundled Intel FTLX8571D3BCV-I3 10GBASE-SR SFP+ modules (850 nm, 300 m multimode). The uplink switch is a Huawei Quidway 9300 whose SFP+ ports carry 10GBASE-LR (1310 nm)…
The poster's Cisco Catalyst C9500-48Y4C switches (IOS XE 16.12.04 after an upgrade) refuse to work with a batch of genuine Cisco SFP-10G-SR modules (VID V03, serials AVD2231D3TE and AVD2231D3RW): 'show inventory' lists them as 'GE ZX' instead of 'SFP+ 10GBASE-SR' and the ports stay non-functional…
While rolling out single-mode fiber between Cisco CBS350-8MGP-2X switches (firmware 3.4.0.17) with SFP-10G-LR modules, the poster hit strange behaviour: the link only comes up if the duplex LC connector is split and the TX fiber is inserted first, then the RX fiber. Inserting the joined LC…
An operator asked how to use non-Intel SFP+ modules for 10G fibre on Intel adapters under Linux. The replies summarised the practical rules: for 82599/X520 class NICs the ixgbe module parameter allowunsupportedsfp must be set, and on dual-port cards it must be given per port…
The poster spent two days trying to bring up a single-mode fiber link between an older Arista switch and a Cisco Catalyst 3650 (IOS-XE 3.7.5) with Cisco GLC-LH-SMD (SFP-LH-SMD) optics; the path runs through five patch cords in the same building and had been tested by the cabling contractor. At…
The poster wanted to use a 40G QSFP+ to 4x10G SFP+ DAC breakout cable on a Cisco Catalyst 9500-32QC-E running IOS XE 17.6.4 (Bengaluru). The 'hw-module breakout' command is rejected; in global configuration only 'hw-module slot' and 'hw-module subslot' are offered. The switch is not running…
The poster, a new owner of a Cisco Nexus 93180YC-EX running NX-OS 7.0(3)I4(7), cannot bring up any 25G link. ipolex SFP28 DAC cables are recognized ('type is SFP-H25GB-CU1M', 'name is OEM', 'part number is SFP-H25G-CU1M', 'nominal bitrate is 25500 MBit/sec', 'DOM is not supported') but the port…
An operator asked about the practical behaviour of Brocade equipment with third-party SFP/SFP+ optics. Experience shared on NANOG: Foundry-heritage platforms (FastIron, NetIron, ICX including ICX7750) generally bring up any MSA-coded module, but the optical-monitor (DDM) function may be unavailable…
The poster planned to install an Intel X520 adapter (Cisco PID N2XX-AIPCI01) into a Cisco UCS C240 server and use Cisco SFP-10G-SR or SFP-10G-LR transceivers, and asked whether the combination has compatibility problems. A later reader asked whether the Cisco SFP-H10GB-CU3M= twinax cable would work…
The poster bought eight J9150D 10G SR SFP+ transceivers for an Aruba 5406R zl2 chassis with a J9993A module. Every module lit the orange LED and logged Unsupported Transceiver. (SelftTest Err#098000), even though the compatibility documents list this combination and the chassis had already been…