Just what it says. I wanted to turn off BIP-110, so I downgraded Knots from 29.3.1 to 29.3.0. I clicked “Re-Index Chain” and now it’s stuck at “Progress 0.00%” for over half-an-hour – and my server was only 5 or 6 blocks behind when this started, so it should’ve taken, what, two minutes at most?
I’ve restarted the Knots service. I’ve restarted the server twice. Still stuck at 0.00%. What’s going on?
I have yet to upgrade my server to the new version of StartOS. I’m still running 0.3.5.1
It’s been yet another hour. Still stuck at 0.00% 
Should I format the server and start over? At this point it’d probably be quicker to re-download the blockchain entirely. If it’s gone 90 minutes and done 0.00%, that means it’s being INSANELY slow…
I would recomend checking the logs to see whats happening
If you told it to reindex the blockchain, it’s going to rebuild the block and chainstate database from genesis.
It’s going to take at least days. Possibly weeks, or even months depending on your hardware specs. Very similar to doing the original sync, except it doesn’t have to re-download blocks you already have. The download part is pretty minimal in the grand scheme of what you told it to do.
The thing that concerned me the most was that it sat there for so long at 0.00%. I finally quit watching it and came back 5 or 6 hours later, whereupon I found it at 36%. So at that point I knew it wasn’t broken, at least.
It wound up taking just a bit under 24 hours.
Nice! You must have one of our newer, more powerful servers. Or a high end DIY machine.
Oh, interesting… I never really thought about it, but it’s a little mini-PC with an Intel N150 CPU (about the equivalent of a 13th-gen Core i7 but with only 4 cores and no hyperthreading), 16GB of DDR4 RAM and a 2TB PCIe-Gen4 SSD, which I guess is pretty strong for a Bitcoin node… Bought it last June for a tick over $300. With today’s crazy prices that thing would probably top $600. LOL!