Performing reindex and wallet rescans

[garethtdavies]

There are two options that are regularly recommended to solve issues those being starting up zcashd with --rescan (solves a lot of balance and missing transaction issues) and starting zcashd with --reindex (for those times when nothing else seems to work...)

In writing docs for this, it is hard to do this in practice when using zec-qt-wallet. For example, the Mac app doesn't give access to the embedded zcashd (or I can't find it 😄).

Even on say Windows, for those users who want to use a GUI it is possibly a little daunting to have to run an external zcashd this way, as well as complicated to explain.

That's a long way of saying, can we get support for doing a rescan and/or reindex. In principle, I would imagine this could work for any zcash.conf config option but those two are the most important. I'm thinking a simple(ish) workaround would be to have an option say "Perform a wallet rescan on startup" that when checked adds the line to zcash.conf which only persists through a single startup as of course, you don't want this running on every launch.

There might be better ways of implementing this and am open to any ideas!

[adityapk00]

This is a good idea. I'll try and implement it next week.

Incidentally, the MacOS embedded zcashd is in zec-qt-wallet.app/Contents/MacOS/zcashd

[garethtdavies]

Incidentally, the MacOS embedded zcashd is in zec-qt-wallet.app/Contents/MacOS/zcashd

Aha, awesome thanks. zcashd wasn't showing up in my find command as I needed to run as sudo. That's great as now at least I can have some consistent docs showing how to do it, even if it is a bit convoluted at present 👍

[adityapk00]

Hey @garethtdavies , @rex4539
I just added a new section in the Settings page where users can do a rescan and/or reindex. Since I've seen you help a lot of people work through these problems, I'd love to get your feedback on whether this will work for people before I release it .

(Note that it's not released yet, you'll have to build from source to see it). Let me know if you need a binary, I can build one as well.

[garethtdavies]

@adityapk00 could you throw up a MacOS build here to test as I seem to have borked my local QT install so that'll be quicker 😄

[garethtdavies]

Scratch that, it was a simple fix and I've built it locally.

[garethtdavies]

Actually, a MacOS build would be helpful as while I can run the updated version I'm having issues starting the embedded zcashd - perhaps due to the renaming?

[rex4539]

I tested the rescan functionality which is fairly quick.

It works as described in the troubleshooting notes.

One thing that would be extremely helpful is to add a progress indicator (bar or text update). I would imagine this is fairly simple to do by polling the progress in debug.log

[adityapk00]

Sorry, I missed the last update, @garethtdavies . Here's the Mac dmg.

Good idea about the progress bar. I'll try to read it from the debug.log
macOS-zecwallet-v0.6.2-preview.dmg.zip

[garethtdavies]

I think you should only enable this option if running the embedded zcashd. If someone is already running an external zcashd then it can be assumed they are capable of starting with an extra flag. I also connect to a remote node via SSH port forwarding and it adds to the file on the local machine so this approach is error-prone.

It also removes the confusing wording on the ZecWallet popup about also needing to restart zcashd as presumably this will be done automatically when closing/reopening ZecWallet.

[garethtdavies]

On the rescan text I'd also say this may take several hours as it can also be pretty quick...

[adityapk00]

Hmm, that's a good point. I hadn't considered the remote scenario, in which case this is clearly doing something stupid.

You're right, it should probably be only for the embedded zcashd

[adityapk00]

Fixed in 0.6.4