# Build and Run `rippled` on Ubuntu

`rippled` is the core peer-to-peer server that manages the XRP Ledger. A `rippled` server can connect to a network of peers, relay cryptographically signed transactions, and maintain a local copy of the complete shared global ledger.

For an overview of `rippled`, see [Operating rippled Servers](tutorial-rippled-setup.html).

Use these instructions to build a `rippled` binary file and run it as a stock `rippled` server on Ubuntu 15.04 or later. These instructions were tested on Ubuntu 16.04 LTS.

For information about building `rippled` for other platforms, see [Builds](https://github.com/ripple/rippled/tree/develop/Builds) in the `rippled` GitHub repository.


## System Requirements

Here are the **minimum** system requirements for building and running `rippled`.

**_To build rippled:_**

* RAM: 8GB

**_To run rippled:_**

* RAM: 4GB
* CPU: 64-bit x86_64, 2+ cores
* Disk: 50GB SSD with 500 IOPS for the database partition
* Network: A fast network connection is preferable

If you are running `rippled` in an Amazon EC2 instance, Ripple recommends selecting a **Type** of **_m3.large_**. If you choose to run a validating `rippled` server, you may need more resources.


## 1. Build `rippled`

These instructions use Ubuntu's APT (Advanced Packaging Tool) to install the software prerequisites you need to build and run `rippled`.

1. Update the list of packages that are available for `apt-get` to install or upgrade.
```
sudo apt-get update
```
2. Upgrade currently installed packages.
```
sudo apt-get -y upgrade
```
3. Install Git.
```
sudo apt-get -y install git
```
4. Install SCons.
```
sudo apt-get -y install scons
```
5. Install Ctags.
```
sudo apt-get -y install ctags
```
6. Install `pkg-config`.
```
sudo apt-get -y install pkg-config
```
7. Install Protocol Buffers.
```
sudo apt-get -y install protobuf-compiler
sudo apt-get -y install libprotobuf-dev
```
8. Install Secure Socket Layer (SSL) toolkit development files.
```
sudo apt-get -y install libssl-dev
```
9. Install `python-software-properties`.
```
sudo apt-get install -y python-software-properties
```
10. Install Boost.
```
sudo add-apt-repository -y ppa:boost-latest/ppa
sudo apt-get -y update
sudo apt-get install -y libboost-all-dev
```
11. Get `rippled` source code.
```
git clone https://github.com/ripple/rippled.git
cd rippled
git checkout master
```
12. Build `rippled` binary executable from source code. This may take about 30 minutes.

    SCons saves the built executable in `rippled/build`.

```
scons
```


## 2. Configure `rippled`

1. Configure `rippled.cfg`.

    `rippled.cfg` is the configuration file for `rippled`.

    You can find the `rippled-example.cfg` example file in `rippled/doc`. See the file for a description of all configuration options. You should be able to connect to the XRP Ledger using the default configuration defined in the example file.

    Put your configured `rippled.cfg` file in `etc/opt/ripple/`.

2. Configure `validators.txt`.

    When you start your `rippled` server for the first time, it uses an initial list of validators defined in `validators.txt` to retrieve validation information and to form its UNL (unique node list). The information in `validators.txt` also enables `rippled` clients to indirectly locate IPs they can use to contact the Ripple network.

    You can find the `validators-example.txt` example file in `rippled/doc`. See the file for a description of all validator options. You should be able to connect to the XRP Ledger using the default validators defined in the example file.

    Put your configured `validators.txt` file in `etc/opt/ripple/`.


## 3. Run `rippled`

To run your stock `rippled` server from the executable you built, using the configurations you defined:
```
cd build
sudo ./rippled
```


### What to Expect

Once you've run `rippled`, here are excerpts of what you can expect to see in your terminal:

```
Loading: "/etc/opt/ripple/rippled.cfg"
Watchdog: Launching child 1
2017-Dec-15 18:27:37 JobQueue:NFO Auto-tuning to 4 validation/transaction/proposal threads for non-validator.
2017-Dec-15 18:27:37 Amendments:DBG Amendment C6970A8B603D8778783B61C0D445C23D1633CCFAEF0D43E7DBCD1521D34BD7C3 is supported.
2017-Dec-15 18:27:37 Amendments:DBG Amendment 4C97EBA926031A7CF7D7B36FDE3ED66DDA5421192D63DE53FFB46E43B9DC8373 is supported.
...
2017-Dec-15 18:27:37 ValidatorList:DBG Loading configured trusted validator list publisher keys
...
2017-Dec-15 18:27:37 ValidatorList:DBG Loading configured validator keys
...
2017-Dec-15 18:27:37 ValidatorSite:DBG Loading configured validator list sites
...
2017-Dec-15 18:27:38 LedgerConsensus:NFO Entering consensus process, watching, synced=no
...
2017-Dec-15 18:27:40 LedgerConsensus:WRN
{
	"accepted" : true,
	"account_hash" : "183D5235C7C1FB5AE67AD2F6CC3B28F5FB86E8C4F89DB50DD85641A96470534E",
	"close_flags" : 0,
	"close_time" : 566677650,
	"close_time_human" : "2017-Dec-15 18:27:30",
	"close_time_resolution" : 30,
	"closed" : true,
	"hash" : "014816C71F4B9AD5924AFBD7B02E0DF1522C4BC4BC45A69F97F51D4F2234FA10",
	"ledger_hash" : "014816C71F4B9AD5924AFBD7B02E0DF1522C4BC4BC45A69F97F51D4F2234FA10",
	"ledger_index" : "2",
	"parent_close_time" : 0,
	"parent_hash" : "AB868A6CFEEC779C2FF845C0AF00A642259986AF40C01976A7F842B6918936C7",
	"seqNum" : "2",
	"totalCoins" : "100000000000000000",
	"total_coins" : "100000000000000000",
	"transaction_hash" : "0000000000000000000000000000000000000000000000000000000000000000"
}
...
2017-Dec-15 18:27:50 NetworkOPs:WRN We are not running on the consensus ledger
2017-Dec-15 18:27:50 LedgerConsensus:WRN Need consensus ledger 8459443546CCBE4E89A41E1D0C17F24FBEA7B344C1ED6A26292B4C5CD19B4321
...
2017-Dec-15 18:38:28 OpenLedger:WRN Offer involves frozen asset
2017-Dec-15 18:38:31 LedgerConsensus:WRN Offer involves frozen asset
```


## Explore Next Steps

Now that you have a stock `rippled` server running, you may want to consider running it as a validating server. For information about validating servers and why you might want to run one, see the [rippled Setup Tutorial](tutorial-rippled-setup.html).

For information about updating and maintaining your `rippled` server, see [Updating rippled](tutorial-rippled-setup.html#updating-rippled).

For information about communicating with your `rippled` server using the `rippled` API, see [rippled](reference-rippled.html).