Install and Run

Before you can start to use Krill you will need to install, configure and run the Krill application somewhere. Please follow the steps below and you will be ready to Get Started with Krill or start Running a Test Environment.


Getting started with Krill is quite easy either building from Cargo or running with Docker. In case you intend to serve your RPKI certificate and ROAs to the world yourself or you want to offer this as a service to others, you will also need to have a public Rsyncd and HTTPS web server available.

Krill can also be se up as a highly available, scalable service using Krill Manager. A 1-Click App on the DigitalOcean Marketplace can set up Krill with all required components, along with integration points for monitoring and log analysis.

Quick Start

For recent Debian and Ubuntu releases you can download, install and run a .deb package from the NLnet Labs package repository.


If you had previously installed Krill using cargo install krill you should first use cargo uninstall krill before installing a .deb package Otherwise the cargo installed binaries for krill and krillc may take precednce in your shell $PATH which could be confusing.

  1. Add the line below that corresponds to your operating system to /etc/apt/sources.list or /etc/apt/sources.list.d/:
deb [arch=amd64] stretch main
deb [arch=amd64] buster main
deb [arch=amd64] xenial main
deb [arch=amd64] bionic main
deb [arch=amd64] focal main
  1. Add the repository signing key to the listed of trusted keys:
wget -qO- | sudo apt-key add -
  1. Install and start Krill:
sudo apt update
sudo apt-get install krill
# review / edit /etc/krill.conf
sudo systemctl enable --now krill

Alternatively, you can build from sources. Assuming you have a newly installed Debian or Ubuntu machine, you will need to install the C toolchain, OpenSSL, curl and Rust. You can then install Krill using Cargo.

After the installation has completed, first create a data directory in a location of your choice. Next, generate a basic configuration file specifying a secret token and make sure to refer to the data directory you just created. Finally, start Krill pointing to your configuration file.

apt install build-essential libssl-dev openssl pkg-config curl
curl --proto '=https' --tlsv1.2 -sSf | sh
source ~/.cargo/env
cargo install krill
mkdir ~/data
krillc config simple --token correct-horse-battery-staple --data ~/data/ > ~/data/krill.conf
krill --config ~/data/krill.conf

Krill now exposes its user interface and API on https://localhost:3000 using a self-signed TLS certificate. You can go to this address in a web browser, accept the certificate warning and start configuring your RPKI Certificate Authority. A Prometheus endpoint is available at /metrics.

If you have an older version of Rust and Krill, you can update via:

rustup update
cargo install --force krill


Using a fully qualified domain name, configuring a real TLS certificate such as Let’s Encrypt, running on a different port and exposing Krill securely to other machines is all possible, but goes beyond the scope of this Quick Start.

Installing with APT/dpkg

Pre-built Debian/Ubuntu packages are available for recent operating system versions on x86_64 platforms. These can be installed using the standard apt, apt-get and dpkg commands as usual.

Unlike with installing with Cargo there is no need to have Rust or a C toolchain installed. Additionally the packages come with systemd service files for easy start/stop of the Krill daemon and with short Linux man pages.


For the oldest platforms, Ubuntu 16.04 LTS and Debian 9, the packaged krill binary is statically linked with OpenSSL 1.1.0 as this is the minimum version required by Krill and is higher than available in the official package repositories for those platforms.

To install Krill from the NLnet Labs package repository:

  1. Run cargo uninstall krill if you previously installed Krill with Cargo.
  2. Add the line below that corresponds to your operating system to /etc/apt/sources.list or /etc/apt/sources.list.d/:
deb [arch=amd64] stretch main
deb [arch=amd64] buster main
deb [arch=amd64] xenial main
deb [arch=amd64] bionic main
deb [arch=amd64] focal main
  1. Add the repository signing key to the listed of trusted keys:
wget -qO- | sudo apt-key add -
  1. Install Krill using sudo apt-get update and sudo apt-get install krill.
  2. Review the generated configuration file at /etc/krill.conf. Pay particular attention to the service_uri and auth_token settings. Tip: The configuration file was generated for you using the krillc config simple command.
  3. Once happy with the settings use sudo systemctl enable --now krill to instruct systemd to enable the Krill service at boot and to start it immediately.

The krill daemon runs as user krill and stores its data in /var/lib/krill. You can manage the Krill daemon using the following commands:

  • Review the Krill logs with journalctl -u krill, or view just the most recent entries with sytemctl status krill.
  • Stop Krill with sudo systemctl stop krill.
  • Learn more about Krill using man krill and man krillc.
  • Upgrade Krill by running apt-get update and apt-get install krill.


Due to issue #280, when upgrading with apt-get it is currently necessary to restart Krill manually after upgrade with sudo systemctl restart krill. This issue will be resolved in the next major release.

Installing with Cargo

There are three things you need for Krill: Rust, a C toolchain and OpenSSL. You can install Krill on any Operating System where you can fulfil these requirements, but we will assume that you will run this on a UNIX-like OS.


The Rust compiler runs on, and compiles to, a great number of platforms, though not all of them are equally supported. The official Rust Platform Support page provides an overview of the various support levels.

While some system distributions include Rust as system packages, Krill relies on a relatively new version of Rust, currently 1.40 or newer. We therefore suggest to use the canonical Rust installation via a tool called rustup.

To install rustup and Rust, simply do:

curl --proto '=https' --tlsv1.2 -sSf | sh

Alternatively, visit the official Rust website for other installation methods.

You can update your Rust installation later by running:

rustup update

For some platforms, rustup cannot provide binary releases to install directly. The Rust Platform Support page lists several platforms where official binary releases are not available, but Rust is still guaranteed to build. For these platforms, automated tests are not run so it’s not guaranteed to produce a working build, but they often work to quite a good degree.

One such example that is especially relevant for the routing community is OpenBSD. On this platform, patches are required to get Rust running correctly, but these are well maintained and offer the latest version of Rust quite quickly.

Rust can be installed on OpenBSD by running:

pkg_add rust

Another example where the standard installation method does not work is CentOS 6, where you will end up with a long list of error messages about missing assembler instructions. This is because the assembler shipped with CentOS 6 is too old.

You can get the necessary version by installing the Developer Toolset 6 from the Software Collections repository. On a virgin system, you can install Rust using these steps:

sudo yum install centos-release-scl
sudo yum install devtoolset-6
scl enable devtoolset-6 bash
curl -sSf | sh
source $HOME/.cargo/env

C Toolchain

Some of the libraries Krill depends on require a C toolchain to be present. Your system probably has some easy way to install the minimum set of packages to build from C sources. For example, apt install build-essential will install everything you need on Debian/Ubuntu.

If you are unsure, try to run cc on a command line and if there’s a complaint about missing input files, you are probably good to go.


Your system will likely have a package manager that will allow you to install OpenSSL in a few easy steps. For Krill, you will need libssl-dev, sometimes called openssl-dev. On Debian-like Linux distributions, this should be as simple as running:

apt install libssl-dev openssl pkg-config


The easiest way to get Krill is to leave it to cargo by saying:

cargo install krill

If you want to update an installed version, you run the same command but add the -f flag, a.k.a. force, to approve overwriting the installed version.

The command will build Krill and install it in the same directory that cargo itself lives in, likely $HOME/.cargo/bin. This means Krill will be in your path, too.

Generate Configuration File

After the installation has completed, there are just two things you need to configure before you can start using Krill. First, you will need a data directory, which will store everything Krill needs to run. Secondly, you will need to create a basic configuration file, specifying a secret token and the location of your data directory.

The first step is to choose where your data directory is going to live and to create it. In this example we are simply creating it in our home directory.

mkdir ~/data

Krill can generate a basic configuration file for you. We are going to specify the two required directives, a secret token and the path to the data directory, and then store it in this directory.

krillc config simple --token correct-horse-battery-staple --data ~/data/ > ~/data/krill.conf


If you wish to run a self-hosted RPKI repository with Krill you will need to use a different krillc config command. See Running a Publication Server for more details.

You can find a full example configuration file with defaults in the GitHub repository.

Start and Stop the Daemon

There is currently no standard script to start and stop Krill. You could use the following example script to start Krill. Make sure to update the DATA_DIR variable to your real data directory, and make sure you saved your krill.conf file there.


nohup $KRILL -c $CONF >$SCRIPT_OUT 2>&1 &
echo $! > $KRILL_PID

You can use the following sample script to stop Krill:


kill `cat $KRILL_PID`

Proxy and HTTPS

Krill uses HTTPS and refuses to do plain HTTP. By default Krill will generate a 2048 bit RSA key and self-signed certificate in /ssl in the data directory when it is first started. Replacing the self-signed certificate with a TLS certificate issued by a CA works, but has not been tested extensively. By default Krill will only be available under https://localhost:3000.

If you need to access the Krill UI or API (also used by the CLI) from another machine you can use use a proxy server such as NGINX or Apache to proxy requests to Krill. This proxy can then also use a proper HTTPS certificate and production grade TLS support.

Proxy Krill UI

The Krill UI and assets are hosted directly under the base path /. So, in order to proxy to the Krill UI you should proxy ALL requests under / to the Krill back-end.

Note that although the UI and API are protected by a token, you should consider further restrictions in your proxy setup - like restrictions on source IP, or you may want to have your own authentication added.

Proxy Krill as Parent

If you delegated resources to child CAs then you will need to ensure that these children can reach your Krill. Child requests for resource certificates are directed to the /rfc6492 under the service_uri that you defined in your configuration file.

Note that contrary to the UI you should not add any additional authentication mechanisms to this location. RFC 6492 uses cryptographically signed messages sent over HTTP and is secure. However, verifying messages and signing responses can be computationally heavy, so if you know the source IP addresses of your child CAs, you may wish to restrict access based on this.

Proxy Krill as Publication Server

If you are running Krill as a Publication Server, then you should read here how to do the Publication Server specific set up.


We recommend that you do not make Krill available to the public internet unless you really need remote access to the UI or API, or you are serving as parent CA or Publication Server for other CAs.

Backup and Restore

To back-up Krill:

  • Stop Krill
  • Backup your data directory
  • Start Krill

We recommend that you stop Krill because there can be a race condition where Krill was just in the middle of saving its state after performing a background operation. We will most likely add a process in future that will allow you to back up Krill in a consistent state while it is running.

To restore Krill just put back your data directory and make sure that you refer to it in the configuration file that you use for your Krill instance.

Used Disk Space

Krill stores all of its data under the DATA_DIR. For users who will operate a CA under an RIR / NIR parent the following sub-directories are relevant:

Dir Purpose
ssl Contains the HTTPS key and cert used by Krill
cas Contains the history of your CA in raw JSON format
rfc6492 Contains all messages exchanged with your parent
rfc8181 Contains all messages exchanged with your repository

The space used by the latter two directories can grow significantly over time. We think it may be a good idea to have an audit trail of all these exchanges. However, if space is a concern you can safely archive or delete the contents of these two directories.

In a future version of Krill we will most likely only store the exchanges where either an error was returned, or your Krill instance asked for a change to be made at the parent side: like requesting a new certificate, or publishing an object. The periodic exchanges where your CA asks the parent for its entitlements will then no longer be logged.

Krill Upgrades

It is our goal that future versions of Krill will continue to work with the configuration files and saved data from version 0.4.1 and above. However, please read the changelog to be sure.

The normal process would be to:

  • Install the new version of Krill
  • Stop the running Krill instance
  • Start Krill again, using the new binary, and the same configuration

Note that after a restart you may see a message like this in your log file:

2020-01-28 13:41:03 [WARN] [krill::commons::eventsourcing::store] Could not
deserialize snapshot json '/root/krill/data/pubd/0/snapshot.json', got error:
'missing field `stats` at line 296 column 1'. Will fall back to events.

You can safely ignore this message. Krill is telling you that the definition of a struct has changed and therefore it cannot use the snapshot.json file that it normally uses for efficiency. Instead, it needs to build up the current state by explicitly re-applying all the events that happened to your CA and/or publication server.