Latest questions from the community.
A Raspberry Pi tool for SFP/SFP+ EEPROM: -r prints connector, transceiver spec, wavelength, vendor, part, serial, date and checksums; -d dumps the whole EEPROM; -c recaculates checksums and offers to write the correct value; -m reads DOM sensors (temperature, voltage, bias, power). A vendor variant…
An open-source hardware and software project to read and modify SFP/SFP+ EEPROM, aimed at changing the OUI and other identity fields so a module works with third-party transceivers where the vendor has not fully disabled write access. It uses a Cypress CY8CKIT-059 board as the USB interface. As of…
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…
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…
Reverse-engineering notes on the SFP Wizard: it reads a module's part number (page A0h bytes 40-55), looks it up in an embedded password database and sends the matching unlock password, falling back to brute force when unmatched. It traces the firmware evolution: v1.0.5 tried only the first…
A notes repository on hacking SFP/QSFP EEPROM: SFPs present EEPROM at I2C 0x50 and DOM plus vendor/password features at 0x51; locked moddules need a 4-byte password written to 0x51 bytes 0x7b-0x7e. It lists several known unlock passwords and evaluates write methods (off-the-shelf coder limited to…
The poster programmed an OEM copper SFP with a 256-byte firmware dump; the switch recognised the type but the module received no data, whereas the original worked, and no password error appeared. It failed on several units. Hardware involved: OEM copper SFP (24C02 EEPROM). Reported…
Users needed to write to password-protected SFP/QSFP/XFP modules from HP, Cisco, Finisar and JDSU. The thread documents the two protection levels: a host/user password protecting the user-writable area (A2h offset 7Bh on SFP, A0h offset 7Bh on QSFP/XFP) and a manufacturer password protecting the…
After a power outage an Aruba Instant On 1930 (24 ports plus 4 SFP) still recognised inserted SFP modules but every SFP port stayed down; inserting a new transceiver made the port LED blink once and then nothing. The poster asked for diagnostics or replacement options. Hardware involved: Aruba…
A Meraki MX95's WAN2 SFP would not link to an upstream Extreme switch, while the same SFP and patch linked to a Netgear switch, which in turn linked to the Extreme. The same happened with an MX85 against an AT&T-provided Ciena device. Cisco-certified and Extreme-certified SFPs were tried in all…
A pre-built HL15 server (Supermicro X11SPH-nCTPF wth Intel X722 SFP+ ports, Rocky Linux) would not link to a UniFi USW-24-POE over a VANDESAIL SFP+ DAC: the switch port stayed Disconnected under every negotiation setting on both sides. After ordering a 10Gtek cable the host reported network driver…
The poster could read and write OEM SFP variants with a REVELPROG and SFP adapter but not three Finisar references, suspecting manufacturer password protection. Finisar only documents the MSA user-EEPROM password in datasheets, not the proprietary manufacturer password, and the same happened with…
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…
