31 votes

What is the fastest way to synchronize the daemon?

The fastest way to achieve this, is to download the current blockchain and import it into the daemon: Step 1: Move into the folder where you downloaded the Monero Gui Wallet, e.g: cd ~/Downloads/...
19 votes
Accepted

My blockchain is stuck, how do I "unstuck" it?

Note that, if you are stuck on block 1288639 (or block 1400001) or a few blocks later, you are using a wrong, outdated, version and you should upgrade to the latest version, which can be found here. ...
  • 14.9k
17 votes
Accepted

I forgot to upgrade (from CLI or GUI v0.13 to CLI or GUI v0.14) and, as a result, accidentally synced to the wrong (alternative) chain

With the most recent version, this particular issue is, fortunately, trivially fixed as follows: GUI Exit the GUI by clicking on the x (right top) and subsequently making sure to stop the daemon as ...
  • 14.9k
15 votes
Accepted

Meaning of "62 days ahead" message after full node has finished synchronizing

The message means that your block height is 62 days ahead of a block which you just were told was mined (on top of a block way back in history). As you verified your block height was correct (as of ...
  • 6,533
14 votes
Accepted

Why does monerod consume so much CPU?

Basically what jwinterm said. I think your best bet, assuming you want to do something else with your computer while catching up rather than catch up ASAP, would be to add --prep-blocks-threads 1 (or ...
  • 2,432
13 votes
Accepted

How do I move the blockchain (data.mdb) to a different directory during (or after) the initial sync without losing the progress?

This is, fortunately, fairly trivial and you won't lose any of the progress. It is done as follows. If you're using the GUI, perform the following steps: Create a new directory on the other/...
  • 14.9k
12 votes

What is the fastest way to synchronize the daemon?

Changing the sync size parameter can have a positive impact in some cases. Start the daemon with: ./monerod --block-sync-size 10 Quoting /u/closenix's test results: I've run some tests: Syncing ...
  • 19.8k
11 votes
Accepted

Why is it faster to synchronize from the network than to import from a raw data file?

Mainly it's a question of available RAM and I/O bandwidth. When you're importing a raw file, reading the raw file takes up disk bandwidth as well as RAM in the filesystem cache. This competes with the ...
  • 4,203
10 votes
Accepted

Why does the option "--verify 0" for monero-blockchain-import not work?

People were abusing --verify 0, using it for files they downloaded from the internet, which is a dangerous thing to do. So it got renamed to --dangerous-unverified-import (prior to this it was named --...
  • 34.6k
9 votes

Why does monerod consume so much CPU?

I think it tries to sync as fast as possible and the verification is CPU intensive. I believe there are options to limit the bandwidth usage in the daemon, or you could just limit the resource usage ...
  • 4,383
9 votes
Accepted

Do I need to sync the entire blockchain before I can send a transaction?

I will try to combine the above answers and my own information into one answer. After recovering my wallet with my mnemonic seed, do I need to synchronize the entire blockchain before I can send a ...
  • 5,656
9 votes
Accepted

Running monerod with --block-sync-size 10 syncs a lot faster, why?

A large block sync size is supposed to make things faster, as some lookups can be made once and reused. However, this uses more memory, and will be slower if it makes the OS start swapping monerod. I ...
  • 34.6k
8 votes
Accepted

What does it mean when the Monero daemon says "LMDB Mapsize increased"?

For performance reasons, LMDB asks the OS to preallocate its storage space in large chunks, instead of growing incrementally as new records are added. Periodically this space must be increased as the ...
  • 4,203
8 votes

Do I need to sync the entire blockchain before I can send a transaction?

Logan is correct, but I'll go into more details about the first question: You technically do not need to sync the whole blockchain, though you'll want to do it to save headaches. What you need to is ...
  • 34.6k
8 votes

Sent to wallet address before synchronization?

It is a common misconception to those new to cryptocurrencies that the coins are "stored" in a wallet. In fact, the coins are stored on the blockchain. They are always there, waiting to be accessed ...
7 votes
Accepted

LMDB conversion vs downloading from scratch

Security wise, it's the same, assuming you do not disable verification on the conversion process (which speeds up a lot, but then if there are problems, they won't be detected). Speedwise, it varies. ...
  • 34.6k
7 votes
Accepted

How long should the GUI wallet take to synchronize?

It is significantly slower with an HDD compared to an SSD. Bandwith is also a significant factor. Yes, if you clicked on the defaults, then you are downloading the entire blockchain. See this ...
6 votes
Accepted

How can I change the default log level from my Monero daemon?

Use the --log-level X argument to bitmonerod. Default log level is 0 (less verbose). The impact on syncing time is minimal on 0, but it can be significant when using a very verbose method like 4, and ...
  • 609
6 votes
Accepted

When syncing Monero's blockchain from scratch, why does it begin fast and end slow?

The speed of transaction validation was reduced with the activation of RingCT at block height 1220517 in early January. Although RingCT transactions still take longer to validate than pre RingCT ...
  • 4,546
6 votes

Monero Height at a standstill

The 100% part of the message means that you are connected only to nodes with at most that height, which is far in the past. Try print_cn and see if you have any peers, and how many. This is odd that ...
  • 34.6k
6 votes

Monerod is syncing 1 block at a time seemingly backwards?

That sounds remarkably normal since Monero's block target is 2 minutes. So you'd be expected to receive a block every two minutes on average. Try running status in monerod. You'll be given the local ...
  • 34.6k
6 votes
Accepted

Changing block-sync-size within GUI or running monerod

First of all, to clarify for the readers, this flag will change the batch of blocks that is fetched to 10, from a default of 200 blocks per batch. How can I do the same thing from the Monero GUI ...
  • 14.9k
5 votes

Should we synchronize blockchain from scratch after every scheduled hard fork?

I think generally just update the binaries and sync from where you left off. I believe the resync from scratch with the most recent binaries (v0.10) were due to significant changes to the database ...
  • 4,383
5 votes

You are now synchronized with the network.

The reason you see that the blockchain is synchronized is because one (or more) of the nodes you are connected to say that you are up to date. Just because one node says you are does not mean that you ...
  • 8,714
5 votes
Accepted

Is there any way to force someone to rescan their wallet?

Not that I know of, but failed transactions and reorgs can get the wallet's idea of what outputs are spent to get out of sync with the blockchain. This does not require a rescan of the blockchain (...
  • 34.6k
5 votes
Accepted

Is it possible to build a BitcoinJ style library that will help enable lightwallets?

Basically yes, a wallet has to scan every block in the blockchain to see if any transactions belong to it. When importing an older wallet, it only needs to scan from the last block known to that old ...
  • 4,203
5 votes

What is the fastest way to synchronize the daemon?

I didn't test that in windows command prompt but in my sync tool i'd gain best results with --block-sync-size 4 --db-sync-mode fastest:sync:8750 update connection :10mbps . Although developers ...
  • 71
5 votes

Synchronizing painfully slowly

To add to the answer provided by fluffyponyza. Hard drive IO is a major bottleneck with synchronizing the blockchain. As an example synchronizing on my desktop took approximately 50 hours on a ...
  • 400
5 votes
Accepted

Syncronisation problem on Geekbox running node from SD card

It sounds like your 32 bit Monero build is invalid, it is computing incorrect hashes and failing to accept valid blocks. If you got this from the official download site, please submit an issue on ...
  • 4,203
5 votes

Error in synchronisation with monerod

The second line of the log indicates Address already in use, which means that the address the daemon is trying to use (0.0.0.0:18080) is already used by some other sofware on your machine. As if there ...
  • 3,314

Only top scored, non community-wiki answers of a minimum length are eligible