Stand-Alone Mode

You can run rippled in stand-alone mode without a consensus of trusted servers. In stand-alone mode, rippled does not communicate with any other servers in the XRP Ledger peer-to-peer network, but you can do most of the same actions on your local server only. Stand-alone provides a method for testing rippled behavior without being tied to the live network. For example, you can test the effects of Amendments before those Amendments have gone into effect across the decentralized network.

When you run rippled in stand-alone mode, you have to tell it what ledger version to start from:

Caution: In stand-alone mode, you must manually advance the ledger.

New Genesis Ledger

In stand-alone mode, you can have rippled create a new genesis ledger. This provides a known state, with none of the ledger history from the production XRP Ledger. (This is very useful for unit tests, among other things.)

  • To start rippled in stand-alone mode with a new genesis ledger, use the -a and --start options:
rippled -a --start --conf=/path/to/rippled.cfg

In a genesis ledger, the genesis address holds all 100 billion XRP. The keys of the genesis address are hardcoded as follows:

Address: rHb9CJAWyB4rj91VRWn96DkukG4bwdtyTh

Secret: snoPBrXtMeMyMHUVTgbuqAfg1SUTb ("masterpassphrase")

Settings in New Genesis Ledgers

In a new genesis ledger, the hard-coded default Reserve is 200 XRP minimum for funding a new address, with an increment of 50 XRP per object in the ledger. These values are higher than the current reserve requirements of the production network. (See also: Fee Voting)

By default, a new genesis ledger has no amendments enabled. If you start a new genesis ledger with --start, the genesis ledger contains an EnableAmendment pseudo-transaction to turn on all amendments natively supported by the rippled server, except for amendments that you explicitly disable in the configuration file. The effects of those amendments are available starting from the very next ledger version. (Reminder: in stand-alone mode, you must advance the ledger manually.) New in: rippled 0.50.0

Load Saved Ledger

You can start with a ledger version that was saved to disk if your rippled server was previously synced with the XRP Ledger peer-to-peer network (either the production network or the Test Net).

1. Start rippled normally.

To load an existing ledger, you must first retrieve that ledger from the network. Start rippled in online mode as normal:

rippled --conf=/path/to/rippled.cfg

2. Wait until rippled is synced.

Use the server_info command to check the state of your server relative to the network. Your server is synced when the server_state value shows any of the following values:

  • full
  • proposing
  • validating

For more information, see Possible Server States.

3. (Optional) Retrieve specific ledger versions.

If you only want the most recent ledger, you can skip this step.

If you want to load a specific historical ledger version, use the ledger_request command to make rippled fetch it. If rippled does not already have the ledger version, you may have to run the ledger_request command multiple times until it has finished retrieving the ledger.

If you want to replay a specific historical ledger version, you must fetch both the ledger version to replay and the ledger version before it. (The previous ledger version sets up the initial state upon which you apply the changes described by the ledger version you replay.)

4. Shut down rippled.

Use the stop command:

rippled stop --conf=/path/to/rippled.cfg

5. Start rippled in stand-alone mode.

To load the most recent ledger version, you can use the -a and --load options when starting the server:

rippled -a --load --conf=/path/to/rippled.cfg

To instead load a specific historical ledger, use the --load parameter along with the --ledger parameter, providing the ledger index or identifying hash of the ledger version to load:

rippled -a --load --ledger 19860944 --conf=/path/to/rippled.cfg

6. Manually advance the ledger.

When you load a ledger with --ledger in stand-alone mode, it goes to the current open ledger, so you must manually advance the ledger:

rippled ledger_accept --conf=/path/to/rippled.cfg

Advancing Ledgers in Stand-Alone Mode

In stand-alone mode, rippled does not communicate to other members of the peer-to-peer network or participate in a consensus process. Instead, you must manually advance the ledger index using the ledger_accept command:

rippled ledger_accept --conf=/path/to/rippled.cfg

In stand-alone mode, rippled makes no distinction between a "closed" ledger version and a "validated" ledger version. (For more information about the difference, see The XRP Ledger Consensus Process.)

Whenever rippled closes a ledger, it reorders the transactions according to a deterministic but hard-to-game algorithm. (This is an important part of consensus, since transactions may arrive at different parts of the network in different order.) When using rippled in stand-alone mode, you should manually advance the ledger before submitting a transaction that depends on the result of a transaction from a different address. Otherwise, the two transactions might be executed in reverse order when the ledger is closed. Note: You can safely submit multiple transactions from a single address to a single ledger, because rippled sorts transactions from the same address in ascending order by Sequence number.