[j-nsp] Link establishment issues with 1Gbps SX/LX SFPs on QFX5110

Timothy Creswick timothy at creswick.eu
Mon Jun 24 17:49:45 EDT 2019

Hi All,

We've been battling with a number of issues getting 1G Base-X links to work on a batch of new QFX5110-48S switches, in use as Fusion devices connected to MX204.

No problems with a variety of 10G and 100G connections. A lot of 1G works fine but we seem to have issues with auto-negotiate with both SX and LX optics. JTAC are a bit lost and we've tried a variety of firmwares with varying success. Turning auto-negotiate off on both sides seems to fix most of this, but that's not viable in a lot of cases where there's a 3rd party involved.

Anyone seen similar and aware of a fix?



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