Top questions
Popular discussions about programming, compatibility and testing of optical transceivers.
The storage box went from Core 13.0-U6.7 to SCALE 24.04 and then on to 24.10, and ever since one port is crawling while its twin on the same card is perfectly happy. The 25G card behaves the same way, which is what makes me doubt my own eyes. Intel X520-DA2 with Intel multimode SFP+ optics, 10G to…
The poster could not find Cisco documentation describing how to set the frequency or ITU channel of a DWDM-SFP10G-C tunable 10G SFP+. A follow-up question asked whether a CPAK-100G-LR4 in a CRS-X 4-port 100GE LAN/OTN card could be tuned to a wavelength and connected directly to a ROADM of an…
Even with allow-unsupportted-transceiver enabled, HPE Aruba 3810M and 2930M switches showed an amber fault for generic SFP+ modules, including ones recoded to masquerade as a J9151A. The author traced the behaviour to HPE's HPIDv2 challenge-response authentication: the module EEPROM carries a flag…
A UCG-Fiber used a UACC-CM-RJ45-MG 10GBASE-T module (port 6, later port 7) to reach a Zyxel XS1930. Whenever the copper cable was disconnected for more than about 40 s or the Zyxel rebooted, the link never came back until the module was pulled for a minute or the gateway rebooted; forcing 10G or 1G…
A customer saw errors on a fibre link and suspected a speed mismatch with a 1G far end. The poster asked whether 10G SFP+ transceivers are backward compatible with 1G, or whether the modules had to be swapped for 1G SFPs to talk to the gigabit device on the other side. Hardware involved: Aruba…
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A QSFPTEK 10GBASE-T SFP+ module installed in port ix1 of a passively cooled Netgate 6100 reported 73 C through DDM although the room was at 20 C; the module is specified for 0-70 C and up to 2.5 W. The poster asked for known-good RJ45 SFP+ modules that stay within spec. Hardware involved: Netgate…
The poster asked whether anyone had used third-party optcis in a Cisco Catalyst 9300 series switch running IOS XE Everest (16.x), and specifically whether the hidden global command 'service unsupported-transceiver', long used on older Catalyst platforms to accept non-Cisco SFPs, still functions on…
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The poster needs a 100GE link between a Cisco NCS55A2-MOD (NC55-MPA-4H-S MPA) and a Cisco Catalyst C9500-48Y4C using a QSFP-100G-CU1M DAC. Both platforms list the cable as supported, yet the link never comes up at the physical level. Because the Catalyst 9500 lacks 100G auto-negotiation (bug…
A FLYPRO SFP-1G-CS-100M 1000BASE-T module in a MikroTik CRS112-8P-4S (RouterOS 6.47.10) was detected but reported no-link with sfp-rx-loss: yes, whatever the far end (MikroTik LHG/RB750Gr3, Ubiquiti, Cisco). Fixed 1G speeds, other module units and rebootts were tried; only a Ubiquiti switch linked…
Mellanox-branded Q-4S28AO03 3 m QSFP28 AOC 1x4 breakout cables (100G with FEC) that worked under Onyx 3.9.1908 stopped linking after an upgrade to Onyx 3.10.x. The ports reported Cable speed not enabled and, with auto speed, Negotiation failure; supported speeds showed 1G/10G/25G but the actual…
Installing a new MES2324FB at a site to replace old hardware. The uplink is 1G fiber to an Alcatel 6224, Foxgate modules from the same batch as at neighboring sites. Setup: Eltex MES2324FB, firmware 4.0.4.7, also tried 4.0.6 - no difference 1G SFP Foxgate on both ends of the link far end - Alcatel…
On two sites a UNAS Pro (UniFi RJ45 SFP+ module) and a UNVR (UniFi fibre SFP+ module) dropped to 1G after every firmware update or power cycle; rebooting the device, the port or the switch did not help, only physically pulling and reinserting the module (or reseating the fibre) restored an…
Small homelab, two second-hand switches and a drawer of optics collected over the years, most of which the hosts refuse because of the vendor code. Recoding has always been the blocker: a proper programmer sits around 369 USD, which is more than I paid for the switches, and the Ubiquiti SFP Wizard…
In a home lab with an Aruba S2500 PoE switch and an Intel X520-DA2, three of thirteen cheaply bought Intel AFBR-703SDZ-IN2 SFP+ modules (around 15 USD each) failed within three months: links dropped with dark activity LEDs, two on the switch side and one on the NIC side. Warm and cold reboots…
All 10G ports on a Netgear M5300-28G3 were used, so the poster asked whether a Cisco 3 m SFP+ DAC (H10GB-CU3M) or Finisar FTLX8571D3BCL 10G SR modules could be used in the switch's 1G SFP ports to add another 10G-capable device at reduced speed. Hardware involved: Netgear M5300-28G3, Cisco…
An operator asked about the practical behaviour of Brocade equipment with third-party SFP/SFP+ optics. Experience shared on NANOG: Foundry-heritage platforms (FastIron, NetIron, ICX including ICX7750) generally bring up any MSA-coded module, but the optical-monitor (DDM) function may be unavailable…
A MikroTik RB4011 connected with an S+DA0001 DAC to a CRS106-1C-5S and a CRS112-8G-IN (all default configuration apart from IP addresses) had no connectivity over the SFP link. The RB4011 SFP+ cage is documented to accept onyl active direct-attach cables, so a passive twinax between it and the two…
In a NANOG discussion about vendor lock-in, an operator described two concrete failures. First, a third-party optic answered I2C reads too slowly; the switch vendor's polling code did not handle the timeout and crashed the linecard control plane, and the vendor refused to treat it as a bug because…
While staging an EX2300-48P and an EX2300-24P (both Junos 18.2R3-S5.3) with non-Juniper SFP+/SFP moules, the 48-port switch recognised the transceivers and created interfaces, but the 24-port switch showed nothing in any of its four uplink ports; show chassis hardware listed PIC 1 as 4x10G SFP/SFP+…
A friend of the poster bought several GLC-T copper SFPs sold as original Cisco, but their serial numbers had an unfamiliar format (00000MTC1719055H, 00000MTC171903XL and similar). 'show interface ethernet 1/45 transceiver sprom' on a Cisco Nexus 5596 lists the module as SFP-1000BASE-T, vendor name…
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The poster asked why third-party SFP modules stopped working after upgrading Cisco switches to IOS 15.2, whereas other vendors accept Cisco or other optics, and whhether this is a technical limitation. No model, log output or interface details were given despite requests. In a later update the…
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An HPE 2920 (J9729A, firmware WB.15.17.0009) with the J9731A 10G expansion module was connected to a DL380 Gen8 with a 560SFP+ NIC using a genuine HPE X242 3 m SFP+ DAC (J9283B). Port A1 with a J9150A SR module worked, but port A2 with the DAC logged Transceiver type not supported in this port and…
A MikroTik CRS312-4C+8XG (RouterOS 7.13.4) and a Ubiquiti USW-Pro-48 (6.6.61) over 20 m OM3 with SR 850 nm SFP+ optics would only negotiate 1G full duplex; 10G attempts failed with no link and occasional Rx Fault on the UniFi side. Several fibre and transceiver combinations were tested and RouterOS…
The poster had an Integra Optics tunable DWDM SFP+ (1528.77-1566.72 nm, 96 channels, 80 km, 10G, sold as Calix/Arista compatible) in an Arista switch. Changing the frequency and configuring the ITU channel through the Arista CLI had no effect: the module kept reporting the same wavelength. The…
The poster wanted to use a 40G QSFP+ to 4x10G SFP+ DAC breakout cable on a Cisco Catalyst 9500-32QC-E running IOS XE 17.6.4 (Bengaluru). The 'hw-module breakout' command is rejected; in global configuration only 'hw-module slot' and 'hw-module subslot' are offered. The switch is not running…
Coming from ordinary office switching, so treat this as a beginner question on the industrial side. I am replacing a long copper run between two panels with fiber on a pair of Stratix 5700 switches and I have never used the SFP slots on these. What I have: two Stratix 5700 switches, one per panel…
The poster's Intel Ethernet Converged Network Adapter X710 would not come up with third-party Fiberxon 10G SFP+ modules: the i40e driver, version 1.2.48, refused to initialise and reported "The driver failed to load because unsupported module type was detected." They asked how to switch on an…
A CRS326-24G-2S+RM and a CCR1009-7G-1C-1S+PC connected with a MikroTik SplusDA0001 SFP+ DAC only linked at 1 Gbps; enabling 10G dropped the link, and the CRS326 in SwOS did not even offer a 10G option. The poster needed SwOS for harrdware LACP. RouterOS/SwOS updates, supout files, and a replacement…
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On an Arista 7050QX running EOS 4.14 the poster tried to use third-party QSFP+ DAC cables; the ports went to errdisable as unqualified transceivers. They patched the XcvrAgent.py agent under /usr/lib/python2.7/site-packages to skip the manufacturer check, which cleared the errdisable state but left…
The poster bought eight J9150D 10G SR SFP+ transceivers for an Aruba 5406R zl2 chassis with a J9993A module. Every module lit the orange LED and logged Unsupported Transceiver. (SelftTest Err#098000), even though the compatibility documents list this combination and the chassis had already been…