Hi,
if you try to upgrade JunOS on a vmhost-running RE (such as RE-S-2X00x6) to a JunOS release which is based on
"Linux WRL9", you apparently need to update the "i40e NVM" firmware first, ref. TSB17603 referenced above.
Apparently you need to ask your support organization to get a copy of the appropriate firmware image file for the
JunOS version you run, assuming it supports the i40e firmware upgrade (see the TSB for details).
Although the TSB doesn't say explicitly that anything newer than or equal to 19.3R1 is based on Linux WRL9,
that appears to indeed be the case, and your experience with 19.4 indicates that version certainly is.
However, my support organization also alerted me about the following
problem report: PR1529710.I interpret (I am merely a customer, so please do not take that as the final truth) the information in that PR such
that at present you need to use either JunOS 20.1R3, 20.2R3 or 20.3R2 (or newer) in order to avoid a serious
(if not catastrophic) JunOS bug when you run with updated i40e NVM firmware, and that it can take in the
order of 24 hours of operation before the effects of that bug manifests itself (if you run with a version which
doesn't have a fix for that PR). It's my sincere hope that the fix for that PR will eventually be applied to other
maintenance branches, although I'm certainly not holding my breath in anticipation.
Regards,
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Havard Eidnes
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