Skip to content

Checkpoints

Since versions 3+ you can sync a fresh chain from 0 much quicker by loading "checkpoints" with your daemon.

How to synchronise the blockchain faster and better

Download the complete checkpoints list from the BLOC-checkpoints GitHub repository This list is updated automatically every day at 12 am (UTC+1)

Setup

  • Right click this link and choose Save link as... to download the latest checkpoints.csv.
  • Place checkpoints.csv in the same folder as your BLOCd daemon
  • You can get BLOCd from here if you don't have it already: https://bloc.money/download
  • Make sure you shut down any GUI wallets, or any other instances of BLOCd.

It should looks like this:

BLOC Folder

Usage

Windows

  • First, open a command prompt in the same directory as BLOCd.
  • This can easily be done by moving to the BLOCd directory in Windows Explorer, then typing cmd in the search bar and hitting enter:

  • Finally, type BLOCd.exe --load-checkpoints checkpoints.csv in the command prompt.

Linux, Apple

  • First, open a command prompt in the same directory as BLOCd.
  • You can use the cd command to change to this directory. For example, cd Downloads/BLOC
  • Alternatively, your file manager may provide the ability to open a terminal in your current directory. Navigate to the folder with BLOCd in, and try right clicking, to see if you can open a terminal there:

Open in terminal

  • Finally, type ./BLOCd --load-checkpoints checkpoints.csv in the terminal.

Expected Output

If you did the steps correctly, you should see something like this output.

2019-Jan-09 07:09:16.687959 INFO    Program Working Directory: ./BLOCd
2019-Jan-09 07:09:16.688363 INFO    Loading Checkpoints for faster initial sync...
2019-Jan-09 07:09:16.762279 INFO    Loaded 155590 checkpoints from checkpoints.csv
2019-Jan-09 07:09:16.762798 INFO    Opening DB in /home/test/.BLOC/DB
2019-Jan-09 07:09:16.764290 INFO    DB not found in /home/test/.BLOC/DB. Creating new DB...
2019-Jan-09 07:09:16.782948 INFO    Initializing core...
2019-Jan-09 07:09:16.784083 INFO    Core initialized OK

Checkpoints

  • BLOCd will then start syncing from checkpoints.
  • If you are using the CLI wallet, then you can just wait for it to finish syncing, and open your wallet.
  • If you are using a GUI wallet, let it finish syncing, close it down by typing exit in the window, then open your GUI wallet.

Once the synchronisation is finished you should see a message like this:

Open in terminal

Common Errors

Invalid checkpoint file format

2018-May-13 12:10:08.325056 INFO    Loading Checkpoints for faster initial sync...
2018-May-13 12:10:08.339667 ERROR   Invalid checkpoint file format
2018-May-13 12:10:08.341758 ERROR   Exception: Failed to load checkpoints
  • If you see output like the above, the file you are opening is either not a .csv file, or hasn't been downloaded correctly.
  • Ensure you downloaded the file by right clicking, and choosing Save link as....
  • If you incorrectly chose the wrong file, you can accidentally download a html page instead.
  • When you open up the file, it should have lots of lines like this:
0,acd5682403287ad25d94769adb80fbcd45de591ecfd5c86d5176bb9a10ff5baa
1,8e2a9807eddd072ab88476e2b96f894f8de83afaae594adc42bc41478cbf6ba0
2,05001da5fd9f0923f52511271805223610c4419e369050696a223f6ce3b3201a
3,55ce2be7b8b63ad2d8075c93c5541d3cb3e069e47f3ba02862b56b0d10240f86

Failed to load checkpoints

2018-May-13 12:14:57.544286 INFO    Loading Checkpoints for faster initial sync...
2018-May-13 12:14:57.544569 ERROR   Could not load checkpoints file: checkpoints.csv
2018-May-13 12:14:57.544823 ERROR   Exception: Failed to load checkpoints
  • If you see output like the above, it means the file isn't present in the directory you are in.
  • Make sure you have placed the checkpoints.csv file in the same directory as BLOCd.

BLOCd.exe is not recognized / No such file or directory

C:\Users\username>BLOCd.exe --load-checkpoints checkpoints.csv
'BLOCd.exe' is not recognized as an internal or external command,
operable program or batch file.

bash: ./BLOCd: No such file or directory

  • If you see output like one of the above, it means your terminal isn't in the same folder as the BLOCd program.
  • You can type pwd to see what folder you are currently in.
  • Try following the steps above to get into the right folder, then try again.
  • If you type ls, you should see the BLOCd program, if you are in the correct folder:
[BLOC] ls
miner  BLOC-service  BLOCWallet  BLOCd

IO error

2018-May-13 11:58:40.857058 INFO    Opening DB in /home/user/.BLOC/DB
2018-May-13 11:58:40.858174 ERROR   DB Error. DB can't be opened in /home/zacuserh/.BLOC/DB. Error: IO error: While lock file: /home/user/.BLOC/DB/LOCK: Resource temporarily unavailable
2018-May-13 11:58:40.873692 ERROR   Exception: IO error
  • If you see output like the above, something else has got the database open already.
  • Make sure you have closed down any other BLOCd's, GUI wallets, and BLOC-service.
  • Use a task manager to help you find any which might be running in the background, then try again.