# Bitcoin MOI genesis snapshot - download files (publish with the 0.1.0 release)

A Bitcoin MOI node needs the snapshot ONCE, at its first start (and again for any `-reindex` / `-reindex-chainstate`).
The chain commits to the file's SHA-256: a wrong or damaged file stops the node with an error, it never starts on bad data.
Holders who only want to keep their coins need nothing; this is for people running a node.

## Files

| file | bytes | sha256 |
|---|---|---|
| moi-snapshot.dat.part0 | 1572864000 | 496cabc893bf1b4fc8b31beeaa51bbe710fcf981d415d0676b5cea9d0541b3cf |
| moi-snapshot.dat.part1 | 1500987038 | 7b4f0945938ec63e9d1f972147b84ede01200a53c2116fe46b45cd7232984d8b |
| moi-snapshot.dat (the two parts joined) | 3073851038 | 89730ede31287759b15e982241337c6434279b89f77745971a20d5caf3f8d499 |
| moi-airdrop-index.dat (optional, see below) | 1496999970 | 1a14f53acd2dce13fb13e2e5121902e6d1473fb912bf627f7731b06cc2f2d848 |
| SHA256SUMS | | the four lines above, for `sha256sum -c` |
| SHA256SUMS.parts | | the two part lines only (used on macOS) |

GitHub release files must be under 2 GiB each, so the snapshot ships as two parts. The joined file is also served over HTTPS
from https://download.bitcoin.moi/ (the same bytes; check the same hash).

## Before you start

- Disk: about 7 GB (3.1 GB snapshot + 3.5 GB coin database); keep 10 GB free during the first start.
- Memory: 4 GB is enough. On a 3 GB machine start once with `-dbcache=100`.
- Data directory (create it if it does not exist yet):
  - Linux: `~/.moi`
  - macOS: `~/Library/Application Support/moi`
  - Windows: `%LOCALAPPDATA%\moi`

## Steps

Download `moi-snapshot.dat.part0`, `moi-snapshot.dat.part1`, `SHA256SUMS` and `SHA256SUMS.parts` into one folder, then:

**Linux**

    sha256sum -c --ignore-missing SHA256SUMS                      # both parts must say OK
    cat moi-snapshot.dat.part0 moi-snapshot.dat.part1 > moi-snapshot.dat
    sha256sum -c --ignore-missing SHA256SUMS                      # moi-snapshot.dat must say OK
    mkdir -p ~/.moi && mv moi-snapshot.dat ~/.moi/

**macOS**

    shasum -a 256 -c SHA256SUMS.parts                             # both parts must say OK
    cat moi-snapshot.dat.part0 moi-snapshot.dat.part1 > moi-snapshot.dat
    shasum -a 256 moi-snapshot.dat                                # must print 89730ede...d499 (full hash in the table)
    mkdir -p ~/Library/Application\ Support/moi && mv moi-snapshot.dat ~/Library/Application\ Support/moi/

**Windows (Command Prompt)**

    copy /b moi-snapshot.dat.part0 + moi-snapshot.dat.part1 moi-snapshot.dat
    certutil -hashfile moi-snapshot.dat SHA256
    rem compare the printed hash with the moi-snapshot.dat line in SHA256SUMS: 89730ede...d499
    mkdir "%LOCALAPPDATA%\moi"
    move moi-snapshot.dat "%LOCALAPPDATA%\moi\"

Another location works too: start the node with `-moisnapshot=<full path to the file>`.

## First start

Start `moid` (or `moi-qt`). The first start loads 43.8 million coins and takes about 4 to 5 minutes. During that time
the node prints nothing and does not answer `moi-cli`: this is normal, do not stop it. If it is stopped anyway, the next
start tells you so; start it once with `-reindex-chainstate` and it rebuilds the coin database from the same file.

The node finds other nodes on its own through the seed list built into the software; no settings are needed.

## Afterwards

- The two `.part` files can be deleted once `moi-snapshot.dat` says OK.
- `moi-snapshot.dat` is only read at the first start. You may delete it afterwards, but keep it if you might ever need
  `-reindex` or `-reindex-chainstate`, which read it again.

## Optional: the airdrop index

`moi-airdrop-index.dat` is only for a node that answers `getairdropproof` for other people (an explorer or proof service).
Start such a node with `-moiairdropindex=<path>`; it needs about 16 GB of memory. Ordinary nodes and holders who claim their
own coins do not need it.