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Popular discussions about programming, compatibility and testing of optical transceivers.
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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…
7votes
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390views
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…
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…
4votes
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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…
Moving my home FTTH line off the operator's ONT and onto a GPON stick in my own router, so that the fibre lands straight in the rack and I keep one box instead of two. The stick is recognised, the port comes up, and then nothing comes back. MikroTik CRS328-24P-4S+, stick in sfp-sfpplus1…
I run a backup storage system in a data center. A pair of DD9900 in HA, network ports on the NDC QLogic. After a reboot or reseating the module, port ethMa stops seeing the transceiver, and it's not a one-off - it's a stable, repeating pattern. Dell DD9900, DD OS 7.2.0.95, HA configuration NDC…
We poll a mixed fleet of ZTE ZXA10 OLTs from LibreNMS and two things are wrong. I suspect they are unrelated, but I am not sure. ZTE ZXA10 C300 on V2.1.0, still in service in an old POP ZTE ZXA10 C620 on V2.0.30, plus a C650 and a C650E one ZTE ZXA10 C320 that used to behave SFP and SFP+ uplinks…
Small home rack, one server and one switch. I replaced an XGS1250-12 with an XS1930-10 and the only thing that did not survive the swap is the server uplink. Zyxel XS1930-10, SFP+ port with media type set to DAC10G Asus XG-C100F in the server 10Gtek CAB-10GSFP-P5M, 5 m passive twinax, AWG26 a…
7votes
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We pulled a pair of G8124E out of a decommissioned rack and I am rebuilding them as the aggregation layer for an internal test environment. Budget for branded optics is zero, so everything goes in with generic 10G SR modules of the type we already run elsewhere. Lenovo RackSwitch G8124E, ex-IBM…
6votes
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My fibre WAN runs into a Turris Omnia and I moved from the ISP box to an XPON stick to drop one hop. The stick is a 2.5G part, the Omnia cage does 2.5G, and everything still lands at 1G. Turris Omnia, Turris OS 7.0.2 HBS, kernel 5.15.148 Luleey LL-XS2510 XPON SFP, RTL960x based, DFP-34X-2C2 family…
On an inexpensive firewall appliance (Intel Atom C3758R, six 1GbE igc ports and two SFP+ cages wired to the CPU) OPNsense showed four ix interfaces instead of two and the SFP+ ports stayed red/down with a copper SFP+ RJ45 module, although the link LEDs lit. ifconfig -v identified ix0/ix1 as the…
7votes
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Small home lab. I flashed a Linksys LGS328C over to OpenWrt SNAPSHOT to get away from the stock web interface. Everything survived the move except one SFP28 port that used to work perfectly well. switch: Linksys LGS328C (Realtek rtl930x), OpenWrt SNAPSHOT module: Dell S28-10G-25G-SR-85C, dual-rate…
Setting up 10G between a server and a TP-Link switch, nothing exotic. The card shows up in the system, driver loads normally, but there's no link on the port at all - no errors, no negotiation attempts. server: Intel X710, four 10GbE SFP+ ports, firmware 9.140.76856 TP-Link switch, SFP+ port cable…
Commissioning a 10G handoff for a customer on a 3930 that was already on site. The module is Ciena's own, pulled from our stock, and the port does come up - but the operational state is UCTF instead of Ena and the uncertified transceiver alarm sits there permanently. The acceptance test includes a…
Running a small virtualization setup: two Proxmox 6 nodes and a target on FreeNAS 11.2. While the HBAs were connected to the target directly, everything ran for months without a single error. Put a used Brocade 200e between them to avoid crossing cables, and that's when it started. two Proxmox 6…
Second hand HPE 5130 for the rack at home, and it arrived with four HPE JD092B X130 10G SFP+ SR modules in the box. I bought new OM4 LC patch cords, wired one SFP+ port to the 10G card in the server, and got absolutely nothing. HPE FlexNetwork 5130 24G PoE+ 4SFP+ EI (JG936A) 4x HPE JD092B X130 10G…
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…
6votes
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I am wiring per-port optical telemetry into monitoring for a couple of Nexus 9000 fabrics. Collection runs through NAPALM, and the getter I lean on is getoptics(). Nexus 9000 leaf and spine pairs QSFP-100G-CWDM4 modules on the fabric links NAPALM with the nxosssh driver, SSH transport, no NX-API…
6votes
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We run a small regional network and pulled a spare 7050T out of stock to use as a DWDM aggregation box. Arista-coded DWDM optics for it quote close to the price of the switch, so we bought third-party DWDM SFP+ instead, and now the switch will not talk to them. Arista 7050T, EOS 4.10.6 generic…