This article provides information about the recall of Junos OS 23.4R2-S6.6 on QFX5120-48Y switches and outlines the impact and recommended actions.

root@qfx5120-48y> show version

Hostname: qfx5120-48y
Model: qfx5120-48y-8c
Junos: 23.4R2-S6.6

Per public TSB104284 [juniper.net].

QFX5000s images having the designation of "... qfx-5e-64-23.4R2-S6.6 ..." have been recalled.

While these issues do not affect other QFX5120 sub-platforms (eg, QFX5120-32C), please discard the 23.4R2-6.6 images.

The new images are available on the download site on 2025-11-26. The image has the designation of "...qfx-5e-23.4R2-S6.10.

23.4R2-S6: Software Release Notification JUNOS software for QFX and EX platforms

Based on the PR details, the reported issue is instability affecting 100GBASE-SR4 optics.

You can check the output >show chassis hardware | match SR, and suggest to discard the version S6.6 and use S6.10 as described in TSB

 Xcvr 48     REV 01  740-061405  1XXXXXXXX      QSFP-100GBASE-SR4