Top questions
Popular discussions about programming, compatibility and testing of optical transceivers.
The poster owned a MikroTik RB962UiGS-5HacT2HnT (hAP ac) with a single SFP cage and had two spare 850 nm modules on hand: a Cisco-branded AFBR-57F5PZ-CS1 and an Intel-branded FTLX8571D3BCVIT1. The ISP delivered the service over a single fibre strand rather than a duplex pair, and the poster wanted…
Juniper-branded SFP modules were intermittently reported as unsupported or not supported in the chassis hardware output right after an EX or MX device booted. Rebooting the device or reseating the SFP made the module recognised again, which was frustrating in production. The poster wanted to know…
Before replacing an old switch with a Cisco Catalyst 9300-M, the poster wanted to know whether the existing SFP could be reused and posted the 'show idprom interface gigabitEthernet 1/1/1' output: Vendor Name CISCO-FINISAR, Vendor Part Number FTLF1318P2BCL-C3, serial FNS15510U5B, 1310 nm, single…
In the poster's data center several Cisco CWDM SFP/GBIC links stopped working: some ports went err-disabled (one with link-flap as the cause) and others simply showed notconnect. Troubleshooting included shut/no shut, reseating the modules, moving the CWDM SFPs to other ports, replacing the patch…
Two Cisco Nexus 93108TC-FX3P switches on NX-OS 9.3(11) are connected with genuine QSFP-100G-CU1M DACs but the link never comes up. The compatibility matrix says the cable is supported from NX-OS 9.3.5. The port config is a plain 'switchport mode trunk' / 'no shutdown', and 'show interface eth1/54…
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…
On a Cisco Nexus N9K-C93180YC-FX, QSFP-40G-SR-BD BiDi modules are not detected at all: nothing appears in the logs when they are inserted and they are absent from 'show interface transceiver', whereas QSFP-40GE-LR4 modules in the same ports are logged and listed normally. Several QSFP-40G-SR-BD…
The poster runs temporary event networks and has twice hit heavy frame errors on 10G links between MikroTik and Cisco switches. About a year earlier a Cisco Catalyst 2960-S with 10G uplinks connected to a MikroTik CRS317-1G-16S+ showed CRC errors on the Cisco side and swapping cables did not help…
While building a trunk between a Cisco Catalyst 3650-48PS and a Catalyst 3560CX-12PC using Cisco GLC-T copper SFPs at both ends, the 3560CX logged '%PHY-4-SFPNOTSUPPORTED: The SFP in Gi0/11 is not supported' and the link would not come up. The poster had already tried 'no errdisable detect cause…
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…
The poster set up several new Cisco Catalyst 9300 switches fitted with C9300-NM-4G network modules, configured GigabitEthernet1/1/1 as a trunk and enabled it, but could not get a link with any of several SFPs. 'show interfaces' reports 'GigabitEthernet1/1/1 is down, line protocol is down…