Only build4-m4 has the cert problem, build6-m4 works fine.

e.g. https://logs.chromium.org/v/?s=chromium%2Fbb%2Ftryserver.chromium.win%2Fwin_upload_clang%2F251%2F%2B%2Frecipes%2Fsteps%2Fpackage_clang%2F0%2Fstdout

dpranke, do you happen to know what is going on?

Dunno offhand, I wonder if there's some inconsistency in the images on the machines.

vhang - can we get someone in labs to check the configs on build{4,6}-m4 ?

I set these up with the same identical image.   Let me see what is up.

This doesn't seem to be reproducible any more. There have been later builds on build4-m4 that didn't fail at that point, e.g.

https://build.chromium.org/p/tryserver.chromium.win/builders/win_upload_clang/builds/252
https://build.chromium.org/p/tryserver.chromium.win/builders/win_upload_clang/builds/256

Okay, let's close this and re-open/file a new bug if it happens again.

Thanks, Peter(s)!