2. Installation
Stork can be installed from pre-built packages or from sources; the following sections describe both methods. Unless there is a good reason to compile from sources, installing from native deb or RPM packages is easier and faster.
2.1. Supported Systems
Stork is tested on the following systems:
Ubuntu 18.04 and 20.04
Fedora 31 and 32
CentOS 8
MacOS 11.3*
* MacOS is not and will not be officially supported. However, many developers on ISC’s team use Macs, so the intention is to keep Stork buildable on this platform.
stork-server
and stork-agent
are written in the Go language; the server uses a PostgreSQL database. In principle, the software can be run
on any POSIX system that has a Go compiler and PostgreSQL. It is likely the software can also be built on other modern systems, but
ISC’s testing capabilities are modest. We encourage users to try running Stork on other OSes not on this list
and report their findings to ISC.
2.2. Installation Prerequisites
The Stork agent does not require any specific dependencies to run. It can be run immediately after installation.
Stork uses the status-get
command to communicate with Kea.
Stork requires the premium Host Commands (host_cmds
) hook library to be loaded by the Kea instance to retrieve host
reservations stored in an external database. Stork works without the Host Commands hook library, but is not able to display
host reservations. Stork can retrieve host reservations stored locally in the Kea configuration without any additional hook
libraries.
Stork requires the open source Statistics Commands (stat_cmds
) hook library to be loaded by the Kea instance to retrieve lease
statistics. Stork works without the Stat Commands hook library, but is not able to show pool utilization and other
statistics.
Stork uses Go implementation to handle TLS connections, certificates, and keys. The secrets are stored in the PostgreSQL
database, in the secret
table.
For the Stork server, a PostgreSQL database (https://www.postgresql.org/) version 10 or later is required. Stork will attempt to run with older versions, but may not work correctly. The general installation procedure for PostgreSQL is OS-specific and is not included here. However, please note that Stork uses pgcrypto extensions, which often come in a separate package. For example, a postgresql-crypto package is required on Fedora and postgresql12-contrib is needed on RHEL and CentOS.
2.3. Stork Tool
The Stork Tool
is a program installed with the Stork Server
, providing commands
to set up server’s database and manage TLS certificates. Using this tool is facultative
because the server runs the database migrations and creates suitable certificates at
startup on its own. However, the tool provides useful commands for inspecting
the current database schema version and downgrading to one of the previous versions.
In addition, in the Preparing Stork Server Database section it is described how the tool can be
conveniently used to create a new database and its credentials without a need to run
SQL commands directly using the psql
program.
The Inspecting Keys and Certificates section describes how to use the tool for TLS certificates management.
Further sections describe different methods for installing the Stork Server from packages.
See: Installing on Debian/Ubuntu and Installing on CentOS/RHEL/Fedora. The stork-tool
program
is installed from the packages together with the server. Alternatively, the tool can be
built from sources:
$ rake build:tool
Please refer to the manual page for usage details: stork-tool - A Tool for Managing Stork Server.
2.4. Preparing Stork Server Database
Before running Stork Server
, a PostgreSQL database and the user with suitable privileges
must be created. Using the stork-tool
is the most convenient way to set up the database.
The following command creates a new database stork
and a user stork
with all privileges
in this database. It also installs the pgcrypto
extension required by the Stork Server.
$ stork-tool db-create --db-name stork --db-user stork
created database and user for the server with the following credentials database_name=stork password=L82B+kJEOyhDoMnZf9qPAGyKjH5Qo/Xb user=stork
By default, stork-tool
connects to the database as user postgres
, a default admin role
in many PostgreSQL installations. If an installation uses a different administrator name, it can
be specified with the --db-maintenance-user
option. For example:
$ stork-tool db-create --db-maintenance-user thomson --db-name stork --db-user stork
created database and user for the server with the following credentials database_name=stork password=L82B+kJEOyhDoMnZf9qPAGyKjH5Qo/Xb user=stork
Similarly, a postgres
database should often exist in a PostgreSQL installation.
However, a different maintenance database can be selected with the --db-maintenance-name
option.
The stork-tool
generates a random password to the created database. This password needs
to be copied into the server environment file or used in the stork-server
command line
to configure the server to use this password while connecting to the database. Use the
--db-password
option with the db-create
command to create a user with a specified
password.
It is also possible to create the database manually (i.e., using the psql
tool).
First, connect to PostgreSQL using psql
and the postgres
administration user. Depending on the system’s configuration, it may require
switching to the user postgres
first, using the su postgres
command.
$ psql postgres
psql (11.5)
Type "help" for help.
postgres=#
Then, prepare the database:
postgres=# CREATE USER stork WITH PASSWORD 'stork';
CREATE ROLE
postgres=# CREATE DATABASE stork;
CREATE DATABASE
postgres=# GRANT ALL PRIVILEGES ON DATABASE stork TO stork;
GRANT
postgres=# \c stork
You are now connected to database "stork" as user "postgres".
stork=# create extension pgcrypto;
CREATE EXTENSION
Note
Make sure the actual password is stronger than “stork”, which is trivial to guess.
Using default passwords is a security risk. Stork puts no restrictions on the
characters used in the database passwords, nor on their length. In particular,
it accepts passwords containing spaces, quotes, double quotes, and other
special characters. Please also consider using the stork-tool
to generate
a random password.
To generate a random password run:
$ stork-tool db-password-gen
generated new database password password=1qWVzmLKy/j40/FVsvjM2ylcFdaFfNxh
The newly created database is not ready for use until necessary database migrations
are executed. The migrations create tables, indexes, triggers, and functions required
by the Stork Server
. As mentioned above, the server can automatically run the
migrations at startup, bringing up the database schema to the latest version. However,
if a user wants to run the migrations before starting the server, they can use the
stork-tool
:
$ stork-tool db-init
$ stork-tool db-up
The up
and down
commands have an optional -t
parameter that specifies the
desired schema version. It is useful when debugging database migrations or downgrading to
one of the earlier Stork versions.
$ # migrate up version 25
$ stork-tool db-up -t 25
$ # migrate down back to version 17
$ stork-tool db-down -t 17
The server requires the latest database version to run, always runs the migration on its own, and refuses to start if the migration fails for any reason. The migration tool is mostly useful for debugging problems with migration, or for migrating the database without actually running the service. For the complete manual page, please see stork-tool - A Tool for Managing Stork Server.
To debug migrations, another useful feature is SQL tracing using the --db-trace-queries
parameter.
The options are either “all” (trace all SQL operations, including migrations and runtime) or “run” (only
trace runtime operations and skip migrations). If specified without any parameters, “all” is assumed. With it enabled,
stork-tool
prints out all its SQL queries on stderr. For example, these commands can be used
to generate an SQL script that updates the schema. Note that for some migrations, the steps are
dependent on the contents of the database, so this is not a universal Stork schema. This parameter
is also supported by the Stork Server
.
$ stork-tool db-down -t 0
$ stork-tool db-up --db-trace-queries 2> stork-schema.txt
2.5. Installing From Packages
Stork packages are stored in repositories located on the Cloudsmith service: https://cloudsmith.io/~isc/repos/stork/packages/. Both Debian/Ubuntu and RPM packages may be found there.
Detailed instructions for setting up the operating system to use this
repository are available under the Set Me Up
button on the
Cloudsmith repository page.
It is possible to install both stork-agent
and stork-server
on
the same machine. It is useful in small deployments with a single
monitored machine, to avoid setting up a dedicated system for the Stork
server. In those cases, however, an operator must consider the potential
impact of the stork-server
on other services running on the same
machine.
2.5.1. Installing the Stork Server
2.5.1.1. Installing on Debian/Ubuntu
The first step for both Debian and Ubuntu is:
$ curl -1sLf 'https://dl.cloudsmith.io/public/isc/stork/cfg/setup/bash.deb.sh' | sudo bash
Next, install the Stork server package:
$ sudo apt install isc-stork-server
2.5.1.2. Installing on CentOS/RHEL/Fedora
The first step for RPM-based distributions is:
$ curl -1sLf 'https://dl.cloudsmith.io/public/isc/stork/cfg/setup/bash.rpm.sh' | sudo bash
Next, install the Stork server package:
$ sudo dnf install isc-stork-server
If dnf
is not available, yum
can be used instead:
$ sudo yum install isc-stork-server
2.5.1.3. Installing on Alpine
The first step for Alpine is:
$ curl -1sLf 'https://dl.cloudsmith.io/public/isc/stork/cfg/setup/setup.alpine.sh' | sh
Next, install the Stork server package:
$ apk add --allow-untrusted isc-stork-server
Warning
For the time being, using the --allow-untrusted
flag is the only option. The FPM packaging tool we use to prepare
the package doesn’t support the signatures for the APK package type.
2.5.1.4. Setup
The following steps are common for Debian-based and RPM-based distributions
using systemd
.
Configure the Stork server settings in /etc/stork/server.env
. The following
settings are required for the database connection (they have a common STORK_DATABASE_
prefix):
STORK_DATABASE_HOST
- the address of a PostgreSQL database; the default islocalhost
STORK_DATABASE_PORT
- the port of a PostgreSQL database; the default is5432
STORK_DATABASE_NAME
- the name of a database; the default isstork
STORK_DATABASE_USER_NAME
- the username for connecting to the database; the default isstork
STORK_DATABASE_PASSWORD
- the password for the username connecting to the database
Note
All of the database connection settings have default values, but we strongly
recommend protecting the database with a non-default and hard-to-guess password
in the production environment. The STORK_DATABASE_PASSWORD
setting must be
adjusted accordingly.
The remaining settings pertain to the server’s RESTful API configuration (the STORK_REST_
prefix):
STORK_REST_HOST
- the IP address on which the server listensSTORK_REST_PORT
- the port number on which the server listens; the default is8080
STORK_REST_TLS_CERTIFICATE
- a file with a certificate to use for secure connectionsSTORK_REST_TLS_PRIVATE_KEY
- a file with a private key to use for secure connectionsSTORK_REST_TLS_CA_CERTIFICATE
- a certificate authority file used for mutual TLS authenticationSTORK_REST_STATIC_FILES_DIR
- a directory with static files served in the user interface
Note
The STORK_REST_STATIC_FILES_DIR
should be set to /usr/share/stork/www
for the Stork Server installed from the binary packages. It’s the default location
for the static content.
The remaining settings pertain to the server’s Prometheus /metrics
endpoint configuration (the STORK_SERVER_
prefix is for general purposes):
STORK_SERVER_ENABLE_METRICS
- enable the Prometheus metrics collector and/metrics
HTTP endpoint
Warning
The Prometheus /metrics
endpoint does not require authentication. Therefore, securing this endpoint
from external access is highly recommended to prevent unauthorized parties from gathering the server’s
metrics. One way to restrict endpoint access is by using an appropriate HTTP proxy configuration
to allow only local access or access from the Prometheus host. Please consult the NGINX example
configuration file shipped with Stork.
With the settings in place, the Stork server service can now be enabled and started:
$ sudo systemctl enable isc-stork-server
$ sudo systemctl start isc-stork-server
To check the status:
$ sudo systemctl status isc-stork-server
Note
By default, the Stork server web service is exposed on port 8080 and
can be tested using a web browser at http://localhost:8080. To use a different IP address or port,
set the STORK_REST_HOST
and STORK_REST_PORT
variables in the /etc/stork/stork.env
file.
The Stork server can be configured to run behind an HTTP reverse proxy
using Nginx
or Apache
. The Stork server package contains an example
configuration file for Nginx
, in /usr/share/stork/examples/nginx-stork.conf
.
The logging colorization is configured analogously to the Stork Agent logging colorization.
2.5.1.5. Securing the Database Connection
The PostgreSQL server can be configured to encrypt communications between the clients and the server. Detailed information on how to enable encryption on the database server, and how to create the suitable certificate and key files, is available in the PostgreSQL documentation.
The Stork server supports secure communications with the database. The following
configuration settings in the server.env
file enable and configure communication
encryption with the database server. They correspond with the SSL settings provided
by libpq
- the native PostgreSQL client library written in C:
STORK_DATABASE_SSLMODE
- the SSL mode for connecting to the database (i.e.,disable
,require
,verify-ca
, orverify-full
); the default isdisable
STORK_DATABASE_SSLCERT
- the location of the SSL certificate used by the server to connect to the databaseSTORK_DATABASE_SSLKEY
- the location of the SSL key used by the server to connect to the databaseSTORK_DATABASE_SSLROOTCERT
- the location of the root certificate file used to verify the database server’s certificate
The default SSL mode setting, disable
, configures the server to use unencrypted
communication with the database. Other settings have the following meanings:
require
- use secure communication but do not verify the server’s identity unless the root certificate location is specified and that certificate exists. If the root certificate exists, the behavior is the same as in the case ofverify-ca
.verify-ca
- use secure communication and verify the server’s identity by checking it against the root certificate stored on the Stork server machine.verify-full
- use secure communication and verify the server’s identity against the root certificate. In addition, check that the server hostname matches the name stored in the certificate.
Specifying the SSL certificate and key location is optional. If they are not
specified, the Stork server uses the ones from the current user’s home
directory: ~/.postgresql/postgresql.crt
and ~/.postgresql/postgresql.key
.
If they are not present, Stork tries to find suitable keys in common system
locations.
Please consult the libpq documentation
for similar libpq
configuration details.
2.5.2. Installing the Stork Agent
There are two ways to install the packaged Stork agent on a monitored machine. The first method is to use the Cloudsmith repository, as with the Stork server installation. The second method, supported since Stork 0.15.0, is to use an installation script provided by the Stork server, which downloads the agent packages embedded in the server package. The preferred installation method depends on the selected agent registration type. Supported registration methods are described in Securing Connections Between the Stork Server and a Stork Agent.
2.5.2.1. Agent Configuration Settings
The following are the Stork agent configuration settings available in the
/etc/stork/agent.env
file after installing the package. All these settings use
the STORK_AGENT_
prefix to indicate that they configure the Stork agent.
The general settings:
STORK_AGENT_HOST
- the IP address of the network interface or DNS name whichstork-agent
should use to receive connections from the server; the default is0.0.0.0
(i.e. listen on all interfaces)STORK_AGENT_PORT
- the port number the agent should use to receive connections from the server; the default is8080
STORK_AGENT_LISTEN_STORK_ONLY
- this enables Stork functionality only, i.e. disables Prometheus exporters; the default isfalse
STORK_AGENT_LISTEN_PROMETHEUS_ONLY
- this enables the Prometheus exporters only, i.e. disables Stork functionality; the default isfalse
STORK_AGENT_SKIP_TLS_CERT_VERIFICATION
- this skips TLS certificate verification whenstork-agent
connects to Kea over TLS and Kea uses self-signed certificates; the default isfalse
The following settings are specific to the Prometheus exporters:
STORK_AGENT_PROMETHEUS_KEA_EXPORTER_ADDRESS
- the IP address or hostname the agent should use to receive the connections from Prometheus fetching Kea statistics; default is0.0.0.0
STORK_AGENT_PROMETHEUS_KEA_EXPORTER_PORT
- the port the agent should use to receive connections from Prometheus when fetching Kea statistics; the default is9547
STORK_AGENT_PROMETHEUS_KEA_EXPORTER_INTERVAL
- specifies how often the agent collects stats from Kea, in seconds; default is10
STORK_AGENT_PROMETHEUS_KEA_EXPORTER_PER_SUBNET_STATS
- enable or disable collecting per subnet stats from Kea; default istrue
(collecting enabled). You can use this option to limit the data passed to Prometheus/Grafana in large networks.STORK_AGENT_PROMETHEUS_BIND9_EXPORTER_ADDRESS
- the IP address or hostname the agent should use to receive the connections from Prometheus fetching BIND9 statistics; default is0.0.0.0
to listen on for incoming Prometheus connection; default is 0.0.0.0STORK_AGENT_PROMETHEUS_BIND9_EXPORTER_PORT
- the port the agent should use to receive the connections from Prometheus fetching BIND9 statistics; default is9119
STORK_AGENT_PROMETHEUS_BIND9_EXPORTER_INTERVAL
- specifies how often the agent collects stats from BIND9, in seconds; default is10
The last setting is used only when Stork agents register in the Stork server using an agent token:
STORK_AGENT_SERVER_URL
- thestork-server
URL used by the agent to send REST commands to the server during agent registration
Warning
stork-server
does not currently support communication with stork-agent
via an IPv6 link-local address with zone ID (e.g., fe80::%eth0
). This means
that the STORK_AGENT_HOST
variable must be set to a DNS name, an IPv4
address, or a non-link-local IPv6 address.
2.5.2.2. Colorization Settings
To control the logging colorization, Stork supports the CLICOLOR
and
CLICOLOR_FORCE
standard UNIX environment variables. When set, the following
rules will be applied:
CLICOLOR_FORCE
!=0
ANSI colors should be enabled no matter what.
CLICOLOR_FORCE
==0
Don’t output ANSI color escape codes.
CLICOLOR_FORCE
is unset andCLICOLOR
==0
Don’t output ANSI color escape codes.
- Otherwise
ANSI colors are enabled if TTY is used.
For example, to disable the output colorization:
rake run:agent CLICOLOR=0
Note
The true
and false
values are also accepted instead of the 1
and 0
.
2.5.2.3. Securing Connections Between the Stork Server and a Stork Agent
Connections between the server and the agents are secured using standard cryptography solutions, i.e. PKI and TLS.
The server generates the required keys and certificates during its first startup. They are used to establish safe, encrypted connections between the server and the agents with authentication at both ends of these connections. The agents use the keys and certificates generated by the server to create agent-side keys and certificates, during the agents’ registration procedure described in the next sections. The private key and CSR certificate generated by an agent and signed by the server are used for authentication and connection encryption.
An agent can be registered in the server using one of the two supported methods:
using an agent token
using a server token
In the first case, an agent generates a token and passes it to the server requesting registration. The server associates the token with the particular agent. A Stork super administrator must approve the registration request in the web UI, ensuring that the token displayed in the UI matches the agent’s token in the logs. The Stork agent is typically installed from the Cloudsmith repository when this registration method is used.
In the second registration method, a server generates a common token for all new registrations. The super admin must copy the token from the UI and paste it into the agent’s terminal during the interactive agent registration procedure. This registration method does not require any additional approval of the agent’s registration request in the web UI. If the pasted server token is correct, the agent should be authorized in the UI when the interactive registration completes. When this registration method is used, the Stork agent is typically installed using a script that downloads the agent packages embedded in the server.
The applicability of the two methods is described in Registration Methods Summary.
The installation and registration processes using each method are described in the subsequent sections.
2.5.2.4. Securing Connections Between stork-agent
and the Kea Control Agent
The Kea Control Agent (CA) may be configured to accept connections only over TLS.
It requires specifying trust-anchor
, cert-file
and key-file
values in
the kea-ctrl-agent.conf
file. For details, see the
Kea Administrator Reference Manual.
The Stork agent can communicate with Kea over TLS, via the same certificates that it uses in communication with the Stork server.
The Stork agent by default requires that the Kea Control Agent provide a trusted TLS certificate.
If Kea uses a self-signed certificate, the Stork agent can be launched with the
--skip-tls-cert-verification
flag or STORK_AGENT_SKIP_TLS_CERT_VERIFICATION
environment
variable set to 1, to disable Kea certificate verification.
The Kea CA accepts only requests signed with a trusted certificate, when the cert-required
parameter
is set to true
in the Kea CA configuration file. In this case, the Stork agent must use valid
certificates; it cannot use self-signed certificates created during Stork agent registration.
Kea 1.9.0 added support for basic HTTP authentication to control access for incoming REST commands over HTTP.
If the Kea CA is configured to use Basic Auth, valid credentials must be provided in the Stork agent
credentials file: /etc/stork/agent-credentials.json
.
By default, this file does not exist, but the /etc/stork/agent-credentials.json.template
file provides example data.
The template file can be renamed by removing the .template
suffix; then the file can be edited
and valid credentials can be provided. The chown
and chmod
commands should be used to set the proper permissions; this
file contains the secrets, and should be readable/writable only by the user running the Stork agent and
any administrators.
Warning
Basic HTTP authentication is weak on its own as there are known dictionary attacks, but those attacks require a “man in the middle” to get access to the HTTP traffic. That can be eliminated by using basic HTTP authentication exclusively over TLS. In fact, if possible, using client certificates for TLS is better than using basic HTTP authentication.
For example:
{
"basic_auth": [
{
"ip": "127.0.0.1",
"port": 8000,
"user": "foo",
"password": "bar"
}
]
}
It contains a single object with a single “basic” key. The “basic” value is a list of the Basic Auth credentials. All credentials must contain the values for four keys:
ip
- the IPv4 or IPv6 address of the Kea CA. It supports IPv6 abbreviations (e.g. “FF:0000::” is the same as “ff::”).port
- the Kea Control Agent port number.user
- the Basic Auth user ID to use in connection with a specific Kea CA.password
- the Basic Auth password to use in connection with a specific Kea CA.
To apply changes in the credentials file, the stork-agent
daemon must be restarted.
If the credentials file is invalid, the Stork agent will run but without Basic Auth support. The notice will be indicated with a specific message in the log.
2.5.2.5. Installation From Cloudsmith and Registration With an Agent Token
This section describes how to install an agent from the Cloudsmith repository and perform the agent’s registration using an agent token.
The Stork agent installation steps are similar to the Stork server installation steps described in Installing on Debian/Ubuntu and Installing on CentOS/RHEL/Fedora. Use one of the following commands depending on the local Linux distribution:
$ sudo apt install isc-stork-agent
$ sudo dnf install isc-stork-agent
instead of the server installation commands.
Next, specify the required settings in the /etc/stork/agent.env
file.
The STORK_AGENT_SERVER_URL
should be the URL on which the server receives the
REST connections, e.g. http://stork-server.example.org:8080
. The
STORK_AGENT_HOST
should point to the agent’s address (or name), e.g.
stork-agent.example.org
. Finally, a non-default agent port can be
specified with the STORK_AGENT_PORT
.
Note
Even though the examples provided in this documentation use the http
scheme, we highly recommend using secure protocols in production
environments. We use http
in the examples because it usually
makes it easier to start testing the software and eliminate all issues
unrelated to the use of https
before it is enabled.
Start the agent service:
$ sudo systemctl enable isc-stork-agent
$ sudo systemctl start isc-stork-agent
To check the status:
$ sudo systemctl status isc-stork-agent
The following log messages should be returned when the agent successfully sends the registration request to the server:
machine registered
stored agent signed cert and CA cert
registration completed successfully
A server administrator must approve the registration request via the
web UI before a machine can be monitored. Visit the Services -> Machines
page in the Stork UI, and click the Unauthorized
button located above the list of machines
on the right side. This list contains all machines pending registration approval.
Before authorizing a machine, ensure that the agent token displayed on this
list is the same as the agent token in the agent’s logs or the
/var/lib/stork-agent/tokens/agent-token.txt
file. If they match,
click on the Action
button and select Authorize
. The machine
should now be visible on the list of authorized machines.
2.5.2.6. Installation With a Script and Registration With a Server Token
This section describes how to install an agent using a script and packages downloaded from the Stork server and register the agent using a server token.
Open Stork in the web browser and log in as a user from the “super admin” group.
Select Services
and then Machines
from the menu. Click on the
How to Install Agent on New Machine
button to display the agent
installation instructions. Copy and paste the commands from the displayed
window into the terminal on the machine where the agent is installed.
These commands are also provided here for convenience:
$ wget http://stork.example.org:8080/stork-install-agent.sh
$ chmod a+x stork-install-agent.sh
$ sudo ./stork-install-agent.sh
stork.example.org
is an example URL for the Stork server;
it must be replaced with the real server URL used in the deployment.
The script downloads an OS-specific agent package from the Stork server (deb or RPM), installs the package, and starts the agent’s registration procedure.
In the agent machine’s terminal, a prompt for a server token is presented:
>>>> Server access token (optional):
The server token is available for a super admin user after clicking on the
How to Install Agent on New Machine
button in the Services -> Machines
page.
Copy the server token from the dialog box and paste it in at the prompt
displayed on the agent machine.
The following prompt appears next:
>>>> IP address or FQDN of the host with Stork Agent (the Stork Server will use it to connect to the Stork Agent):
Specify an IP address or fully qualified domain name (FQDN) that the server should use to reach out to an agent via the secure gRPC channel.
When asked for the port:
>>>> Port number that Stork Agent will use to listen on [8080]:
specify the port number for the gRPC connections, or hit Enter if the default port 8080 matches the local settings.
If the registration is successful, the following messages are displayed:
machine ping over TLS: OK
registration completed successfully
Unlike with Installation From Cloudsmith and Registration With an Agent Token, this registration method does not require approval via the web UI. The machine should already be listed among the authorized machines.
2.5.2.7. Installation With a Script and Registration With an Agent Token
This section describes how to install an agent using a script and packages downloaded from the Stork server and perform the agent’s registration using an agent token. It is an interactive alternative to the procedure described in Installation From Cloudsmith and Registration With an Agent Token.
Start the interactive registration procedure following the steps in the Installation With a Script and Registration With a Server Token section.
In the agent machine’s terminal, a prompt for a server token is presented:
>>>> Server access token (optional):
Because this registration method does not use the server token, do not type anything in this prompt. Hit Enter to move on.
The following prompt appears next:
>>>> IP address or FQDN of the host with Stork Agent (the Stork Server will use it to connect to the Stork Agent):
Specify an IP address or FQDN that the server should use to reach out to an agent via the secure gRPC channel.
When asked for the port:
>>>> Port number that Stork Agent will use to listen on [8080]:
specify the port number for the gRPC connections, or hit Enter if the default port 8080 matches the local settings.
The following log messages should be returned when the agent successfully sends the registration request to the server:
machine registered
stored agent signed cert and CA cert
registration completed successfully
As with Installation From Cloudsmith and Registration With an Agent Token, the agent’s registration request must be approved in the UI to start monitoring the newly registered machine.
2.5.2.8. Installation From Cloudsmith and Registration With a Server Token
This section describes how to install an agent from the Cloudsmith repository and perform the agent’s registration using a server token. It is an alternative to the procedure described in Installation With a Script and Registration With a Server Token.
The Stork agent installation steps are similar to the Stork server installation steps described in Installing on Debian/Ubuntu and Installing on CentOS/RHEL/Fedora. Use one of the following commands, depending on the Linux distribution:
$ sudo apt install isc-stork-agent
$ sudo dnf install isc-stork-agent
Start the agent service:
$ sudo systemctl enable isc-stork-agent
$ sudo systemctl start isc-stork-agent
To check the status:
$ sudo systemctl status isc-stork-agent
Start the interactive registration procedure with the following command:
$ su stork-agent -s /bin/sh -c 'stork-agent register -u http://stork.example.org:8080'
The last parameter should be the appropriate Stork server URL.
Follow the same registration steps described in Installation With a Script and Registration With a Server Token.
2.5.2.9. Registration Methods Summary
Stork supports two different agent-registration methods, described above. Both methods can be used interchangeably, and it is often a matter of preference which one the administrator selects. However, the agent token registration may be more suitable in some situations. This method requires a server URL, agent address (or name), and agent port as registration settings. If they are known upfront, it is possible to prepare a system (or container) image with the agent offline. After starting the image, the agent sends the registration request to the server and awaits authorization in the web UI.
The agent registration with the server token is always manual. It requires copying the token from the web UI, logging into the agent, and pasting the token. Therefore, the registration using the server token is not appropriate when it is impossible or awkward to access the machine’s terminal, e.g. in Docker. On the other hand, the registration using the server token is more straightforward because it does not require unauthorized agents’ approval via the web UI.
If the server token leaks, it poses a risk that rogue agents might register. In that case, the administrator should regenerate the token to prevent the uncontrolled registration of new agents. Regeneration of the token does not affect already-registered agents. The new token must be used for any new registrations.
The server token can be regenerated in the How to Install Agent on New Machine
dialog box available after navigating to the Services -> Machines
page.
2.5.2.10. Agent Setup Summary
After successful agent setup, the agent periodically tries to detect installed Kea DHCP or BIND9 services on the system. If it finds them, they are reported to the Stork server when it connects to the agent.
Further configuration and usage of the Stork server and the Stork agent are described in the Using Stork chapter.
2.5.2.11. Inspecting Keys and Certificates
The Stork server maintains TLS keys and certificates internally to secure the
communication between stork-server
and any agents. They can be inspected
and exported using stork-tool
, with a command such as:
$ stork-tool cert-export --db-url postgresql://user:pass@localhost/dbname -f srvcert -o srv-cert.pem
The above command may fail if the database password contains any characters requiring URL encoding. In this case, a command line with multiple switches can be used instead:
$ stork-tool cert-export --db-user user --db-password pass --db-host localhost --db-name dbname -f srvcert -o srv-cert.pem
The certificates and secret keys can be inspected using OpenSSL, using commands such as
openssl x509 -noout -text -in srv-cert.pem
(for the certificates) and
openssl ec -noout -text -in cakey
(for the keys).
There are five secrets that can be
exported or imported: the Certificate Authority secret key (cakey
), the Certificate Authority certificate (cacert
),
the Stork server private key (srvkey
), the Stork server certificate (srvcert
), and a server token (srvtkn
).
For more details, please see stork-tool - A Tool for Managing Stork Server.
2.5.2.12. Using External Keys and Certificates
It is possible to use external TLS keys and certificates. They can be imported
to the Stork server using stork-tool
:
$ stork-tool cert-import --db-url postgresql://user:pass@localhost/dbname -f srvcert -i srv-cert.pem
The above command may fail if the database password contains any characters requiring URL encoding. In this case, a command line with multiple switches can be used instead:
$ stork-tool cert-import --db-user user --db-password pass --db-host localhost --db-name dbname -f srvcert -i srv-cert.pem
Both the Certificate Authority key and the Certificate Authority certificate must be changed at the same time, as the certificate depends on the key. If they are changed, then the server key and certificate must also be changed.
The ability to use external certificates and keys is considered experimental.
For more details, please see stork-tool - A Tool for Managing Stork Server.
2.5.3. Upgrading
Due to the new security model introduced with TLS in Stork 0.15.0, upgrades from versions 0.14.0 and earlier require the agents to be re-registered.
The server upgrade procedure is the same as the initial installation procedure.
Install the new packages on the server. Installation scripts in the deb/RPM package will perform the required database and other migrations.
2.6. Installing From Sources
2.6.1. Compilation Prerequisites
Usually, it is more convenient to install Stork using native packages. See Supported Systems and Installing From Packages for details regarding supported systems. However, the sources can also be built separately.
The dependencies that need to be installed to build the Stork sources are:
Rake
Java Runtime Environment (only if building natively, not using Docker)
Docker (only if running in containers; this is needed to build the demo)
Other dependencies are installed automatically in a local directory by Rake tasks, which does not require root privileges. If the demo environment will be run, Docker is needed but not Java; Docker installs Java within a container.
For details about the environment, please see the Stork wiki at https://gitlab.isc.org/isc-projects/stork/-/wikis/Install .
2.6.2. Download Sources
The Stork sources are available in ISC’s GitLab instance: https://gitlab.isc.org/isc-projects/stork.
To get the latest sources invoke:
$ git clone https://gitlab.isc.org/isc-projects/stork
2.6.3. Building
There are two Stork components:
stork-agent
- this is a binary, written in Gostork-server
- this is comprised of two parts: - backend service - a binary, written in Go - frontend - an Angular application written in Typescript
All components can be built using the following command:
$ rake build
The agent component is installed using this command:
$ rake install:agent
and the server component with this command:
$ rake install:server
By default, all components are installed in the specific system directories;
this is useful for installation in a production environment. For the testing
purposes tt can be customized via the DEST
variable, e.g.:
$ rake install:server DEST=/home/user/stork
2.6.4. Installing on FreeBSD
Stork is not regularly tested on FreeBSD but can be installed on this operating system with the manual steps provided below.
The first step is the installation of packages from the repository:
pkg install ruby
pkg install rubygem-rake
pkg install wget
pkg install openjdk11-jre
pkg install node14
pkg install npm-node14
npm install -g npm
pkg install python3
pkg install protobuf
pkg install gcc
pkg install gtar
The utility to build the packages requires the GNU tar in PATH. The BSD tar isn’t compatible. We need to rename the existing executable.
mv /usr/bin/tar /usr/bin/bsdtar
ln -s /usr/local/bin/gtar /usr/bin/tar
Stork build system can install all remaining dependencies automatically.
The binary packages can be built using:
rake build:server_pkg
rake build:agent_pkg
The output binaries will be located in the dist/pkgs/
directory and can be
installed using the pkg install
command.
2.6.5. Installing on OpenBSD
Stork is not regularly tested on OpenBSD but can be installed on this operating system with the manual steps provided below. The installation guide is similar to FreeBSD one.
The first step is the installation of packages from the repository:
pkg_add ruby
ln -s /usr/local/bin/gem31 /usr/local/bin/gem
gem install --user-install rake
pkg_add wget
pkg_add jdk
pkg_add node
pkg_add unzip
pkg_add protobuf
pkg_add gcc
pkg_add go
Stork requires Golang version 1.18 or later.
Stork build system can install all remaining dependencies automatically.
Unfortunately, there is no possibility to build the binary packages for OpenBSD. But it is possible to build the contents of the packages (executables, UI, man, and docs).
rake build:server_dist
rake build:agent_dist
The output files will be located in the dist/
directory.
2.7. Integration With Prometheus and Grafana
Stork can optionally be integrated with Prometheus, an open source monitoring and alerting toolkit, and Grafana, an easy-to-view analytics platform for querying, visualization, and alerting. Grafana requires external data storage. Prometheus is currently the only environment supported by both Stork and Grafana. It is possible to use Prometheus without Grafana, but using Grafana requires Prometheus.
2.7.1. Prometheus Integration
The Stork agent, by default, makes
Kea statistics, as well as some BIND 9 statistics, available in a format understandable by Prometheus. In Prometheus nomenclature, the
Stork Agent works as a Prometheus “exporter.” If the Prometheus server is available, it can
be configured to monitor Stork agents. To enable stork-agent
monitoring, the prometheus.yml
file (which is typically stored in /etc/prometheus/
, but this may vary depending on the
installation) must be edited to add the following entries:
# statistics from Kea
- job_name: 'kea'
static_configs:
- targets: ['agent-kea.example.org:9547', 'agent-kea6.example.org:9547', ... ]
# statistics from bind9
- job_name: 'bind9'
static_configs:
- targets: ['agent-bind9.example.org:9119', 'another-bind9.example.org:9119', ... ]
By default, the Stork agent exports Kea data on TCP port 9547 and BIND 9 data on TCP port 9119. This can be configured using command-line parameters, or the Prometheus export can be disabled altogether. For details, see the Stork agent manual page at stork-agent - Stork Agent to Monitor BIND 9 and Kea services.
The Stork server can also be optionally integrated, but Prometheus support for it is disabled by default. To enable it,
run the server with the -m
or --metrics
flag or set the STORK_SERVER_ENABLE_METRICS
environment variable.
Next, update the prometheus.yml
file:
# statistics from Stork Server
- job_name: 'storkserver'
static_configs:
- targets: ['server.example.org:8080']
The Stork server exports metrics on the assigned HTTP/HTTPS port (defined via the --rest-port
flag).
Note
The Prometheus client periodically collects metrics from the clients (stork-server
or stork-agent
, for example),
via an HTTP call. By convention, the endpoint that shares the metrics has the /metrics
path.
This endpoint returns data in Prometheus-specific format.
Warning
The Prometheus /metrics
endpoint does not require authentication. Therefore, securing this endpoint
from external access is highly recommended to prevent unauthorized parties from gathering the server’s
metrics. One way to restrict endpoint access is by using an appropriate HTTP proxy configuration
to allow only local access or access from the Prometheus host. Please consult the NGINX example
configuration file shipped with Stork.
After restarting, the Prometheus web interface can be used to inspect whether the statistics have been exported properly.
Kea statistics use the kea_
prefix (e.g. kea_dhcp4_addresses_assigned_total
); BIND 9
statistics will eventually use the bind_
prefix (e.g. bind_incoming_queries_tcp
); and Stork server statistics use the
storkserver_
prefix.
2.7.2. Alerting in Prometheus
Prometheus provides the ability to configure alerting. A good starting point is the Prometheus documentation on alerting. Briefly, the three main steps are: configure the Alertmanager; configure Prometheus to talk to the Alertmanager; and define the alerting rules in Prometheus. There are no specific requirements or recommendations, as these are very deployment-dependent. The following is an incomplete list of ideas that could be considered:
The
storkserver_auth_unreachable_machine_total
metric is reported bystork-server
and shows the number of unreachable machines. Its value under normal circumstances should be zero. Configuring an alert for non-zero values may be the best indicator of a large-scale problem, such as a whole VM or server becoming unavailable.The
storkserver_auth_authorized_machine_total
andstorkserver_auth_unauthorized_machine_total
metrics may be used to monitor situations when new machines (e.g. by automated VM cloning) may appear in the network or existing machines may disappear.The
kea_dhcp4_addresses_assigned_total
metric, along withkea_dhcp4_addresses_total
, can be used to calculate pool utilization. If the server allocates all available addresses, it will not be able to handle new devices, which is one of the most common failure cases of the DHCPv4 server. Depending on the deployment specifics, a threshold alert when the pool utilization approaches 100% should be seriously considered.Contrary to popular belief, DHCPv6 can also run out of resources, in particular with prefix delegation (PD). The
kea_dhcp6_pd_assigned_total
metric divided bykea_dhcp6_pd_total
can be considered an indicator of PD pool utilization. It is an important metric if PD is being used.
The alerting mechanism configured in Prometheus has the relative advantage of not requiring an additional component (Grafana). The alerting rules are defined in a text file using simple YAML syntax. For details, see the Prometheus documentation on alerting rules. One potentially important feature is Prometheus’ ability to automatically discover available Alertmanager instances, which may be helpful in various redundancy considerations. The Alertmanager provides a rich list of receivers, which are the actual notification mechanisms used: email, PagerDuty, Pushover, Slack, Opsgenie, webhook, WeChat, and more.
ISC makes no specific recommendations between Prometheus or Grafana. This is a deployment consideration.
2.7.3. Grafana Integration
Stork provides several Grafana templates that can easily be imported, available in the grafana/
directory of the
Stork source code. The currently available templates are bind9-resolver.json
, kea-dhcp4.json
, and kea-dhcp6.json
. Grafana integration requires three steps:
1. Prometheus must be added as a data source. This can be done in several ways, including using the user interface to edit the Grafana configuration files. This is the easiest method; for details, see the Grafana documentation about Prometheus integration. Using the Grafana user interface, select Configuration, select Data Sources, click “Add data source,” and choose Prometheus; then specify the necessary parameters to connect to the Prometheus instance. In test environments, the only necessary parameter is the URL, but authentication is also desirable in most production deployments.
2. Import the existing dashboard. In the Grafana UI, click Dashboards, then Manage, then Import, and select one of the templates, e.g.
kea-dhcp4.json
. Make sure to select the Prometheus data source added in the previous step. Once imported, the
dashboard can be tweaked as needed.
3. Once Grafana is configured, go to the Stork user interface, log in as “super admin”, click Settings in the Configuration menu, and then add the URLs for Grafana and Prometheus that point to the installations. Once this is done, Stork will be able to show links for subnets leading to specific subnets.
Alternatively, a Prometheus data source can be added by editing datasource.yaml
(typically stored in /etc/grafana
,
but this may vary depending on the installation) and adding entries similar to this one:
datasources:
- name: Stork-Prometheus instance
type: prometheus
access: proxy
url: http://prometheus.example.org:9090
isDefault: true
editable: false
The Grafana dashboard files can also be copied to /var/lib/grafana/dashboards/
(again, the exact location may vary depending on the
installation).
Example dashboards with some live data can be seen in the Stork screenshots gallery .
2.7.4. Subnet Identification
The Kea Control Agent shares subnet statistics labeled with the internal Kea IDs.
The Prometheus/Grafana subnet labels depend on the installed Kea hooks.
By default, the internal, numeric Kea IDs are used.
However, if the subnet_cmds
hook is installed, then the numeric IDs are resolved to subnet prefixes.
This makes the Grafana dashboard more human-friendly and descriptive.
2.7.5. Alerting in Grafana
Grafana offers multiple alerting mechanism options that can be used with Stork; users are encouraged to see the Grafana page on alerting.
The list of notification channels (i.e. the delivery mechanisms) is extensive, as it supports email, webhook, Prometheus’ Alertmanager, PagerDuty, Slack, Telegram, Discord, Google Hangouts, Kafka REST Proxy, Microsoft Teams, Opsgenie, Pushover, and more. Existing dashboards provided by Stork can be modified and new dashboards can be created. Grafana first requires a notification channel to be configured (Alerting -> Notifications Channel menu). Once configured, existing panels can be edited with alert rules. One caveat is that most panels in the Stork dashboards use template variables, which are not supported in alerting. This stackoverflow thread discusses several ways to overcome this limitation.
Compared to Prometheus alerting, Grafana alerting is a bit more user-friendly. The alerts are set using a web interface, with a flexible approach that allows custom notification messages, such as instructions on what to do when receiving an alert, information on how to treat situations where received data is null or there is a timeout, etc.
The defined alerts are considered an integral part of a dashboard. This may be a factor in a deployment configuration, e.g. the dashboard can be tweaked to specific needs and then deployed to multiple sites.