Popular discussions about programming, compatibility and testing of optical transceivers.
I look after the access layer at a small ISP and I want our two GPON OLTs to show up in monitoring the same way everything else does. The wish list is not exotic: how hot the chassis runs, CPU and RAM load, counters per port, and the part I actually caare about, the optical side. That means Rx/Tx…
I look after a small office network and put in a DrayTek VigorSwitch FX2120 to get a 10G core. Both 10G links, to the router and to the NAS, came up on their own within seconds. What I cannot do is get a single 1G device onto the switch through the SFP+ cages. Switch: DrayTek VigorSwitch FX2120…
Trying to replace the ISP terminal in my home rack with a GPON stick straight in the router, so the fibre lands in one box instead of two. The stick is recognised, and that is where the good news ends. Turris Omnia on Turris OS 5.0.3, stock kernel Huawei MA5671A GPON stick with unlocked firmware…
We are bringing up a pair of 8360-32Y4C as leaves and the downlink plan is deliberately mixed: mostly 25G to servers, a couple of 50G ports to a compute chassis, and a few slow copper drops for out-of-band gear. Because the SFP56 downlinks are grouped and the speed is set per group, I want to…
I finally moved my VDSL2 line off the ISP box and terminated it on the Turris Omnia itself, mostly so that PPPoE runs on the router instead of on a second device in bridge mode. The setup part was pleasant: seat the stick in the cage and the WAN interface simply moves onto the module, leaving the…
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…
Standing up 25G uplinks from a QFX5120-48Y towards a second switch and a couple of new servers. Before I hand the segment over I want the link settings written down properly, and I cannot find where auto-negotiation lives on these ports. Juniper QFX5120-48Y 25G optics in the SFP28 cages et…
We are lighting a handful of channels over one metro pair with passive mux and demux at both ends, 100 GHz plan. Everything I can actually source is fixed-wavelength DWDM SFP+, a separate part number per channel, and keeping spares that way is getting silly. 10G aggregation at both ends, SFP+ cages…
Joining two buildings over a Nortel pair that has been in place longer than I have. The plan was simply to light the existing house fibre between the two switches and be done with it, but port 23 will not come up on either end. Two Nortel ERS 5510-24T, software 4.0.2.02 1000SX SFP GBICs, one in…
The poster needed to connect a MikroTik CRS328-4C-20S-4S+RM to an HP 1820-24G-PoE+ over 200-500 m of outdoor aerial fibre and asked which SFP modules to buy and how to verify compatibility before purchase. The HP compatibility table listed only J4859C as a single-mode SFP, while MikroTik offered…
We hand customer circuits off on MRV OptiSwitch demarcation boxes - mostly OS906, with a few OS904 and OS912 left on older builds. When a ticket comes in about a circuit that is down or flapping, I want two things over SSH before anyone drives out: what module is actually sitting in the port…
An embedded device with a 10GbE SFP transceiver kept logging power warnings above 800 mW and occasional errors when fed by an NVIDIA/Mellanox MMA2P00-AS 10/25G transceiver over a 2 m OM3 LC patch. The poster assumed transmit power is negotiated between the two ends and asked whether a failed…
I look after a two-building site and the access switches were replaced with Aruba 2540s a while back. The fibre between the buildings has not been touched, but since the swap the uplink refuses to come up. Aruba 2540 on our side, ports 51 and 52 used for the uplinks Aruba J4858D 1000SX in the 2540…
A link between two of our sites: about 27 km of single-mode fiber, MES3324F on both ends. Installed a pair of 1550 nm FANG HANG SFPs sold as 40-km modules. The link comes up, lives for a few dozen seconds, and drops, over and over, until the port gets blocked. 2 x Eltex MES3324F, firmware 4.0.7 SFP…
We had a 200 m OM4 backbone pulled between two buildings a while back and I am trying to light it with kit we already own. Both ends are 2530s, both modules are the HPE part, and the link simply will not come up. 2x Aruba 2530-48G 2x J4858C 1000SX, port 51 on each side roughly 200 m of freshly…
I swapped the ISP ONU for an ODI DFP-34X-2C2 GPON stick in my Turris Omnia so the fibre terminates in the router instead of another box on the shelf. That part worked: the line is registered, traffic flows, no complaints. The problem is the rate. It never goes above 1Gbps, and 2.5G was the whole…
The poster asked how to test fibre cables from a switch. The guidance covers reading optical levels with show interfaces transceiver / show controllers, comparing TX and RX at both ends, and recognising that a reading of -40, -50 or -80 dBm means no signal is being received. Hardware involved…
We are a small regional ISP rebuilding the optics budget for next year. Every 10G spare on our shelf is coded for exactly one platform, so the spares pool is roughly three times larger than our failure rate justifies. The idea on the table is to buy re-codable modules and code them ourselves as…
A network operator received QFX3500 switches that would not bring up thhird-party SFP+ transceivers even though a Juniper sales engineer had said they would work. JTAC stated that non-Juniper SFP+ optics would never be supported on the platform. The switch detected the presence of the module but…
A site decommission left me with a drawer of pulled Cisco optics, a mix of GBICs, 1G SFPs and 10G SFP+, and I have to decide which of them go back into production and which go in the bin. The GBICs I have put aside for now, since nothing on the bench takes them, so everything below is about the SFP…
We poll a handful of Nokia 7705 aggregation routers in LibreNMS and I wanted optical DOM off them for the usual reason - catching a span going soft before the customer notices. Discovery never finishes on those devices. Nokia 7705 running TiMOS LibreNMS 26.3.1 Ordinary single-lane 1G SFPs in the…
We are refreshing a pair of aggregation closets and the optics line is the part management keeps poking at. The switches are EXOS boxes and the plan was to fill the 40G uplinks with generic QSFP+ DACs, the same way we already do on the access ports. Then someone on the team dug up a note about a…
Home setup, everything in one rack. I want to connect the NAS to the switch faster than gigabit, but I don't want to run fiber: the distance is about five meters, a plain patch cord covers it. D-Link DGS-1250-28X switch, SFP+ ports free TerraMaster F4-424 Max NAS, copper RJ-45 port short Cat6a…
A Dell-branded Intel X520-DA2 with Flypro 10GBASE-T SFP+ modules showed no carrier (or no interface at all) on Debian and on FreeBSD-based OPNsense because the card rejects unapproved modules. The post collects the per-OS fixes and the permanent EEPROM approach. Hardware involved: Dell-branded…
Homelab switch: a D-Link DGS-1210-28 revision F1 that I flashed with OpenWrt so I could stop fighting the stock web UI. Everything works except the last four ports, which are the copper/fibre combo ones. Switch: D-Link DGS-1210-28 rev F1 Firmware: OpenWrt 21.02.0-rc3 (r16172-2aba3e9784) Ports…
I do small batches of module recoding for integrators, and until now everything on my bench has been SFP-shaped: read the 256 bytes at A0h with the serial ID in the first half, read A2h for the diagnostics and thresholds, write the identification block, done. A customer has now turned up with 100G…
One host in a blade chassis went to ESXi 8.0 U3 and came back with no Fibre Channel at all. The datastores are gone, the adapters are not in the storage adapter list, and nothing logs in on the fabric side for those ports. The rest of the cluster is untouched and still sees the same LUNs. blade…
A FreeNAS build on a Supermicro X11SPM-TPF board would not recognise a Ubiquiti UF-RJ45-10G SFP+ copper module in the on-board SFP+ cage, although the switch side showed link. The poster asked for BIOS settings or a compatible 10G RJ45 transceiver. Hardware involved: Supermicro X11SPM-TPF, Intel…
An ADDON JD097C-AO SFP+ DAC worked between two US-48-500W (firmware 3.3.11.3850) but not from a US-48-500W to a US-16-XG (3.7.39.6089): no link lights on either side and forcing 10G made no difference, although mca-dump on the XG showed the module fully parsed (sfpfound true, vendor ADDON, part…
I look after a mixed Zyxel estate on one site and I am putting together a vrey basic optical health check for the fibre uplinks: temperature and Rx power per port, so I can see a link degrading before the users report it. What is involved: Zyxel GS1910, older access switch with SFP uplinks Zyxel…
The poster wanted to use a Finisar FCLF8521P2BTL 1000BASE-T copper SFP in an Intel X710-DA2 running NVM 7.1. Intel's X710/XXV710/XL710 Feature Support Matrix (rev. 3.4, Nov 2019, doc 332191-024) lists single-speed SFP 1GBASE-T transceivers with support limited to Finisar FCLF-8521-3, Kinnex A…
Home setup, and I am trying to get rid of the ISP router on a Cosmote GPON line. The idea is to run the fibre straight into the UDM-Pro and let the stick do the ONU job, but the provider only accepts the session if the 12-character serial and the device model string of the old CPE are presented, so…
Small tower site: an RB4011 in a ventilated roadside cabinet feeding a couple of radios, with one 10GBASE-T copper hop over to the switch because there was already cable in the duct. The port drops out on warm afternoons and comes back at night, which points fairly clearly at the module rather than…
The postter had an existing multimode fibre run of about 200 m that could not be replaced and only single-moode SFP modules available. The question was whether a 1G single-mode SFP pair would establish a stable link over multimode fibre, and what the practical limits were. The thread also raised…
We inherited a pair of Connectrix DS-7720B (Brocade G720) for a new fabric, and I haven't got anywhere near zoning yet, because not one of the double density ports will come up. Every single one of them says the same thing in switchshow: What is in the rack: Connectrix DS-7720B / Brocade G720…
I run pfSense on a small box with a Chelsio T580 and I want one of the QSFP+ ports feeding four 10G hosts instead of a single 40G link. The breakout cable is still on its way, so I would rather have the card in the right mode before it lands. pfSense box, Chelsio T580, one QSFP+ port sitting on a…
Two Jetson Thor devices achieved 100G connectivity directly but with poor speed, and when each was connected to a 100G switch no link formed, although the same optics and cables passed a 100G loopback test against a different switch. The poster wondered whether insufficient speed was breaking…
We run packet capture on a handful of Napatech cards and I am putting together the optics order for the next rack. Before spending anything I want to understand what the qualified module list actually means in practice, because the wording leaves room for interpretation. Napatech NT40E3 and NT20E3…
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…
We hand over industrial cabinets with the customer's own monitoring on top, so readable DDMI on the uplink ports is part of the acceptance list. On an RGS200-12P the two ports that matter refuse to print anything at all after DDMI is enabled, even though both links are up and forwarding. Zyxel…
A new UDM Pro replaced a USG-3; plugging its LAN SFP+ port into the free SFP port of a UniFi Switch 24 with a known-good SFP+ DAC (taken from a working switch-to-switch link) gave no link on either UDM Pro port, and manually setting the UDM Pro port to 1 Gbps did not help. Several other users…
A Huawei S6700 iStack did not form because the optical modules on the dedicated stacking ports 45-48 were of different types; the platform requires identical transceivers on those ports. The four ports 45-48 are the fixed stacking ports, and mixing, for example, an SR module on one and an LR module…
We have a leased dark pair between two POPs, roughly 115 km, and both ends land on a Cisco Catalyst 6506. The requirement is modest: one gigabit, no DWDM, no channel plan, just a working point to point link. What came back when I asked Cisco how to build it from their own catalogue was an…
We took over a small aggregation site and one of the 10G uplinks has not come up since the module in it was swapped. The module is listed as incompatible with the CRS226, so that is where suspicion landed first, but the readings do not look like a rejected module to me. MikroTik CRS226 at the…
A Chelsio CC2-S320E-SR (110-1114-30) dual-port SFP+ card recognised by TrueNAS would not link to a Dell PowerConnect 6224 through a QSFPTEK 0.5 m passive DAC: no link lights and status: no carrier, even after assigning IPs to cxgb0/cxgb1. Looping the DAC between two switch ports worked, and looping…
A CSS326 (SwOS 2.12) uplinked to an RB4011 throuhg an FS.com 10G active DAC accumulated Rx MAC errors, Rx FCS errors and Tx pauses. Cleaning the DAC connectosr did not help, and the poster asked whether SwOS had SFP+ bugs. Hardware involved: MikroTik CSS326-24G-2S+, MikroTik RB4011, FS.com 10G…
A Cisco Catalyst 3850-24XS with an SFP-10G-LR (1310 nm) connects over a single-mode cross-connect to a Tier-1 carrier's layer-2 DWDM equipment in the same data center. When the carrier shuts the circuit down, TenGigabitEthernet2/0/23 goes 'down, line protocol is down (notconnect)' yet 'show…
After upgrading to Proxmox VE 8 with the 6.x kernel, on-board Intel X553 SFP+ ports that worked on kernel 5.15.108 showed NO-CARRIER even with the cable and module connected. The regression was traced to an upstream ixgbe commit (565736048bd5) that broke auto-negotiation handling for X550/X553…
The thread starter documented that 82599-based X520 cards carry an undocumented EEPROM bit (IXGBEDEVICECAPSALLOWANYSFP, lowest bit of the capability word at byte offset 0x58, typically 0xFC locked / 0xFD unlocked) that decides whether non-Intel active SFP+ modules are accepted on ESXi and Windows…
A 2920-48G-PoE+ (J9729A) rejected a J9283B 3 m SFP+ DAC with 00536 FFI: port 45 Transceiver type not supported in this port even though HP lists the cable as compatible; the same cable worked in a 2530 with SFP+ slots. Firmware had been updated without effect. A later reader noticed an old J9283B…
