What was the most challenging issue you solved?
Figuring out how to get a critical (couldnโt go live without it1) call reporting Oracle database to work on Solaris after the vendorโs top-level tech support and half a dozen other people could not get it to function. I did this mere hours before the deadline.
No Google. All brain (and some man pages).
I later phoned the vendor and told them how to fix their own misconfigured garbage.
I miss working in Solaris and using CDE. Donโt want anything to do with Oracle ever again, though.