Top questions
Popular discussions about programming, compatibility and testing of optical transceivers.
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…
5votes
4comments
276views
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…
4votes
5comments
132views
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…
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…
3votes
2comments
107views
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…
6votes
3comments
120views
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…
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…
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…
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…
4votes
3comments
124views
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…
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 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…