Popular discussions about programming, compatibility and testing of optical transceivers.
We are bringing up a leaf on an Accton AS9716-32D running SONiC master (build master.207726). Four of the 400G-capable ports have to run at 100G towards a firewall pair, and not one of them will link. Accton AS9716-32D, SONiC master.207726 INNOLIGHT TR-FC13R-N00 QSFP28 LR4 in the switch cage…
Rebuilding aggregation at one of our sites: a CRS326-24S+2Q+RM takes the custmer SFP+ ports and uplinks over 40G into a Huawei S6720. Short run inside the same rack, so a passive DAC rather than optics. MikroTik CRS326-24S+2Q+RM, QSFP+ port qsfpplus1-1 Huawei S6720-54C-EI-48S-AC, plain 40GE port…
Standing up a small traffic-test bench next to the production fabric, and the tester ports will not come up over copper at all. HP 5900 40G switch, JC772A HP JG328A 40G QSFP+ direct attach cable Ixia Xcellon-Multis QSFP 40/10GE load module Spirent TestCenter 40G module, tried as a second opinion HP…
A tutorial on recoding SFP/SFP+ EEPROM so a module works with a different vendor's switch. It uses a Cisco Twingig housing to reach the SFP I2C pins and wires four lines from the Pi GPIO (3.3 V, GND, SDA on GPIO3, SCL on GPIO5). It shows detecting 0x50 (and optional 0x51 DOM) with i2cdetect, points…
Discussion of why re-coded modules fail Cisco validation: Cisco SFPs carry a unique signature tied to each serial number in bytes 96-127, and editing vendor name or serial makes the signature no longer match, so the switch rejects the module unless the signature is regenerated. Hardware involved…
A small toolset that reads and writes SFP EEPROM over I2C with a CH341A programmer plus an I2C sniffer. The author found that sigrok/PulseView did not work with the analyser, that a v1.0.5 SFP coder firmware reported success while silently not writing the module (proven by I2C traces), and that the…
I am writing a small poller that pulls temperature, voltage, bias and optical power straight off the modules on our whitebox boxes, so we get a trend line instead of someone eyeballing a link after it has already started erroring. The NOS prints pretty values, but I want the raw numbers with the…
FS Box V2 is a firmware/coding tool kit for optical transceivers and DAC/AOC cables. It reprograms a module's compatibility code so it is accepted by a target switch platform, letting engineers adjust coding in the field or when a switch is upgraded to a version that no longer accepts the old code…
A reference post on the memory layout used when programming transceivers: SFP blocks A0h (serial ID/vendor, often write-protected) and A2h (diagnostics, page-select byte 7Fh, page 00h/01h user-writable); QSFP block A0h with page-select 7Fh, page 00h identity write-protected and page 03h user…
We are consolidating a pair of R630s onto 10G and the cabling to the top of the rack is copper, so instead of pulling fibre I put 10GBASE-T SFP+ modules into the X520 cards. The switch end takes them without a word. The servers refuse to. Dell PowerEdge R630, Intel X520 (82599), dual port FS…
Home setup. The fibre handoff from my provider is a 1G BiDi module and I would like it in the firewall itself instead of kepeing a switch in front of the box just to convert media. Protectli Vault 6 running pfSense, X710 ports, ixl driver the provider-supplied 1G BiDi module, an EZConn…
After upgrading OPNsense from the 21.x series to 22.7 a 10G SFP+ port stopped working with interface is disabled due to unsupported sfp; the newer Intel driver actively disables unrecognised modules. The poster tried to set ixgbe.allowunsupportedsfp=1 as a system tunable, which was not accepted…
Servicing a small office network, two buildings linked by a single single-mode fiber that contractors pulled. The job was supposed to take half an hour: bring up a gigabit link between the switches in the two buildings. It's been two weeks and it still won't come up. What's installed: main…
On Zyxel XGS4600 switches, 10G and 1G SFP+ transceivers (including an FS.com DWDM-SFP10G-80) intermittently stopped transmitting; only removing and reinserting the module restored the link. Transceiver statistics at that moment showed TX power -inf dBm, voltage at the 3.00 V low alarm and TX bias…
I keep a small pool of shared modules: the nodes are scattered around the city, and I have to recode SFP modules for almost every switch that isn't mine. With gigabit modules the routine has been solid for a long time, but a 10G one just stopped me cold. What's on the bench: a programmer with an…
