5. Troubleshooting
5.1. stork-agent
This section describes the solutions for some common issues with the Stork agent.
- Issue:
A machine is authorized in the Stork server successfully, but there are no applications.
- Description:
The user has installed and started
stork-server
andstork-agent
and authorized the machine. The “Last Refreshed” column has a value on the Machines page and the “Error” column value shows no errors, but the “Daemons” column is still blank. The “Application” section on the specific Machine page is also blank.- Solution:
Make sure that the daemons are running:
Kea Control Agent, Kea DHCPv4 server, and/or Kea DHCPv6 server
BIND 9
Stork looks for the processes named
kea-ctrl-agent
(for Kea) ornamed
(for BIND 9). Make sure those processes are running and are named appropriately. Use theps aux
(or similar) command to determine whether the processes are running. Currently, Stork does not support detecting off-line services. If BIND 9 is located in an uncommon location and the Stork agent is unable to detect it, there are several steps that may be helpful. First, enable the DEBUG logging level, so the agent will print more detailed information about locations being checked.Stork attempts the next four actions, in order:
Try to parse the
-c
parameter of the running process;Use the STORK_AGENT_BIND9_CONFIG environment variable;
Try to parse the output of the
named -V
command;Try to find the named.conf file in the default locations.
The
STORK_AGENT_BIND9_CONFIG
environment variable may be defined to specify the exact location of the BIND 9 configuration file.For BIND 9, make sure that the rndc channel is enabled. By default it is enabled, even if the
controls
clause is missing. Stork is able to detect default values, so typically there is no administrative action required, unless the rndc channel was explicitly disabled. Make sure the rndc key is readable by the Stork agent.Also, make sure that BIND 9 has the statistics channel enabled, by adding a
statistics-channels
entry. Typically, this looks like the following:statistics-channels { inet 127.0.0.1 port 8053 allow { 127.0.0.1; }; };
but it may vary greatly, depending on a given setup. Please consult the BIND 9 Administrator Reference Manual (ARM) for details.
- Explanation:
If the “Last Refreshed” column has a value, and the “Error” column value has no errors, the communication between
stork-server
andstork-agent
works correctly, which implies that the cause of the problem is between the Stork agent and the daemons. The most likely issue is that none of the Kea/BIND 9 daemons are running.stork-agent
communicates with the BIND 9 daemon directly; however, it communicates with the Kea DHCPv4 and Kea DHCPv6 servers via the Kea Control Agent. If only the “CA” daemon is displayed in the Stork interface, the Kea Control Agent is running, but the DHCP daemons are not.
- Issue:
After starting the Stork agent, it gets stuck in an infinite “sleeping” loop.
- Description:
stork-agent
is running with server support (the--listen-prometheus-only
flag is unused). Thetry to register agent in Stork server
message is displayed initially, but the agent only prints the recurringsleeping for 10 seconds before next registration attempt
message.- Solution 1:
stork-server
is not running. Start the Stork server first and restart thestork-agent
daemon.- Solution 2:
The configured server URL in
stork-agent
is invalid. Correct the URL and restart the agent.
- Issue:
stork-agent
starts but returns theloaded server cert: /var/lib/stork-agent/certs/cert.pem and key: /var/lib/stork-agent/certs/key.pem
message.- Description:
stork-agent
runs correctly and its registration is successful. After thestarted serving Stork Agent
message, the agent prints the recurring message about loading server certs. The network traffic analysis to the server reveals that it rejects all packets from the agent (TLS HELLO handshake failed).- Solution:
Re-register the agent to regenerate the certificates, using the
stork-agent register
command.- Explanation:
The
/var/lib/stork-agent/certs/ca.pem
file is missing or corrupted. The re-registration removes old files and creates new ones.
- Issue:
The cert PEM file is not loaded.
- Description:
The agent fails to start and prints an
open /var/lib/stork-agent/certs/cert.pem: no such file or directory could not load cert PEM file: /var/lib/stork-agent/certs/cert.pem
error message.- Solution:
Re-register the agent to regenerate the certificates, using the
stork-agent register
command.
- Issue:
A connection problem to the DHCP daemon(s) is occurring.
- Description:
The agent prints the message
problem with connecting to dhcp daemon: unable to forward command to the dhcp6 service: No such file or directory. The server is likely to be offline
.- Solution 1:
Try to start the Kea service:
systemctl start kea-dhcp4 kea-dhcp6
.- Solution 2:
Ensure that the
control-socket
entry is specified in the Kea DHCP configuration file (kea-dhcp4.conf
orkea-dhcp6.conf
).- Explanation:
The
kea-dhcp4.service
orkea-dhcp6.service
(depending on the service type in the message) may not be running. If the DHCP daemon is running and operational (it allocates the leases), but the problem is still occurring, inspect the DHCP daemon configuration file (kea-dhcp4.conf
orkea-dhcp6.conf
). The file must contain the top-levelcontrol-socket
property with valid content. See the DHCPv4 or DHCPv6 section of the Kea ARM for details. This property is missing by default if Kea is installed from the Debian/Ubuntu repository. To avoid this and similar problems, we recommend using ISC’s official packages on Cloudsmith.
- Issue:
stork-agent
receives aremote error: tls: certificate required
message from the Kea Control Agent.- Description:
The Stork agent and the Kea Control Agent are running, but they cannot establish a connection. The
stork-agent
log contains the error message mentioned above.- Solution:
Install valid TLS certificates in
stork-agent
or set thecert-required
value in/etc/kea/kea-ctrl-agent.conf
tofalse
.- Explanation:
By default,
stork-agent
does not use TLS when it connects to Kea. If the Kea Control Agent configuration includes thecert-required
value set totrue
, it requires the Stork agent to use secure connections with valid, trusted TLS certificates. It can be turned off by setting thecert-required
value tofalse
when using self-signed certificates, or the Stork agent TLS credentials can be replaced with trusted ones.
- Issue:
The Kea Control Agent returns a
Kea error response - status: 401, message: Unauthorized
message.- Description:
The Stork agent and the Kea Control Agent are running, but they cannot connect. The
stork-agent
logs contain similar messages:failed to parse responses from Kea: { "result": 401, "text": "Unauthorized" }
orKea error response - status: 401, message: Unauthorized
.- Solution:
Update the
/etc/stork/agent-credentials.json
file with the valid user/password credentials.- Explanation:
The Kea Control Agent can be configured to use Basic Authentication. If it is enabled, valid credentials must be provided in the
stork-agent
configuration. Verify that this file exists and contains a valid username, password, and IP address.
- Issue:
During the registration process,
stork-agent
returns aproblem with registering machine: cannot parse address
message.- Description:
Stork is configured to use an IPv6 link-local address. The agent prints the
try to register agent in Stork server
message and then the above error. The agent exists with a fatal status.- Solution:
Use a global IPv6 or an IPv4 address.
- Explanation:
IPv6 link-local addresses are not supported by
stork-server
.
- Issue:
A protocol problem occurs during the agent registration.
- Description:
During the registration process,
stork-agent
prints aproblem with registering machine: Post "/api/machines": unsupported protocol scheme ""
message.- Solution:
The
--server-url
argument is provided in the wrong format; it must be a canonical URL. It should begin with the protocol (http://
orhttps://
), contain the host (DNS name or IP address; for IPv6 escape them with square brackets), and end with the port (delimited from the host by a colon). For example:http://storkserver:8080
.
- Issue:
The values in
/etc/stork/agent.env
or/etc/stork/agent-credentials.json
were changed, butstork-agent
does not notice the changes.- Solution 1:
Restart the daemon.
- Solution 2:
Send the SIGHUP signal to the
stork-agent
process.- Explanation:
stork-agent
reads configurations at startup or after receiving the SIGHUP signal.
- Issue:
The values in
/etc/stork/agent.env
were changed and the Stork agent was restarted, but it still uses the default values.- Description:
The agent is running using the
stork-agent
command. It uses the parameters passed from the command line but ignores the/etc/stork/agent.env
file entries. If the agent is running as the systemd daemon, it uses the expected values.- Solution 1:
Load the environment variables from the
/etc/stork/agent.env
file before running Stork agent. For example, run. /etc/stork/agent.env
.- Solution 2:
Run the Stork agent with the
--use-env-file
switch.- Explanation:
The
/etc/stork/agent.env
file contains the environment variables, butstork-agent
does not automatically load them unless the--use-env-file flag
is set; the file must be loaded manually. The defaultsystemd
service unit is configured to load this file before starting the agent.
- Issue:
Stork shows only the Kea Control Agent tab on the Apps page. It detects no Kea DHCP servers, although the DHCP daemons are running and allocating leases.
- Description:
There is only a single tab titled “CA” on the Kea Apps page, but no data about any DHCP daemon or DDNS. The Kea Control Agent and Kea DHCPv4 or Kea DHCPv6 daemon are running and serve leases. The Stork agent log includes the
The Kea application has no DHCP daemons configured
message.- Solution:
The
kea-ctrl-agent.conf
file is missing thecontrol-sockets
property.- Explanation:
Stork detects Kea components using the control socket list from the Kea Control Agent configuration file. The list must be configured properly to allow Stork to send commands to Kea daemons. See the Kea ARM <https://kea.readthedocs.io/en/latest/arm/agent.html#configuration> for details. This property is missing by default if Kea is installed from the Debian/Ubuntu repository. To avoid this and similar problems, we recommend using ISC’s official packages on Cloudsmith.
- Issue:
The Stork agent fails to start and returns the following error:
failed to load hooks from directory: '[HOOK DIRECTORY]': plugin.Open("[HOOK DIRECTORY]/[FILENAME]"): [HOOK DIRECTORY]/[FILENAME]: file too short
orfailed to load hooks from directory: '[HOOK DIRECTORY]': plugin.Open("[HOOK DIRECTORY]/[FILENAME]"): [HOOK DIRECTORY]/[FILENAME]: invalid ELF header
.- Solution:
Remove the given file from the hook directory.
- Explanation:
The file under a given path is not a valid Stork hook.
- Issue:
The Stork agent fails to start and returns the following error:
Cannot start the Stork Agent: incompatible hook version: 1.0.0
.- Solution:
Update the given hook.
- Explanation:
The hook is out-of-date and is incompatible with the Stork core application.
- Issue:
The Stork agent fails to start and returns the following error:
Cannot start the Stork Agent: plugin: symbol Version not found in plugin
.- Solution:
Remove or fix the given file.
- Explanation:
The hook directory contains the Go plugin, but not the hook; the Go hook does not contain a required symbol.
- Issue:
The Stork agent fails to start and returns the following error:
Cannot start the Stork Agent: hook library dedicated for another program: Stork Server
.- Solution:
Move the incompatible hooks to a separate directory.
- Explanation:
The Stork agent requires the hook directory to contain only agent hooks. The error message indicates that the hook directory contains hooks dedicated to the Stork server.
- Issue:
The Stork agent starts but the hooks are not loaded. The logs include the following message:
Cannot find plugin paths in: /usr/lib/stork-agent/hooks: cannot list hook directory: /usr/lib/stork-agent/hooks: open /usr/lib/stork-agent/hooks: no such file or directory
.- Solution:
Create the hook directory or change the path in the configuration.
- Explanation:
The hook directory does not exist.
- Issue:
The Stork agent fails to start and returns the following error:
Cannot start the Stork Agent: open [HOOK DIRECTORY]: permission denied cannot list hook directory
.- Solution:
Grant read access to the hook directory to the
stork-agent
user.- Explanation:
The hook directory is not readable.
- Issue:
The Stork agent fails to start and returns the following error:
Cannot start the Stork Agent: readdirent [HOOK DIRECTORY]/[FILENAME]: not a directory cannot list hook directory
.- Solution:
Change the hook directory path.
- Explanation:
A file was found instead of a directory under the given hook directory path.
5.2. stork-server
This section describes the solutions for some common issues with the Stork server.
- Issue:
The values in
/etc/stork/server.env
were changed, butstork-server
does not notice the changes.- Solution 1:
Restart the daemon.
- Solution 2:
Send the SIGHUP signal to the
stork-server
process.- Explanation:
stork-server
reads configurations at startup or after receiving the SIGHUP signal.
- Issue:
The values in
/etc/stork/server.env
were changed and the Stork server was restarted, but it still uses the default values.- Description:
The server is running using the
stork-server
command. It uses the parameters passed from the command line but ignores the/etc/stork/server.env
file entries. If the server is running as thesystemd
daemon, it uses the expected values.- Solution 1:
Load the environment variables from the
/etc/stork/server.env
file before running the Stork server. For example, run. /etc/stork/server.env
.- Solution 2:
Run the Stork server with the
--use-env-file
switch.- Explanation:
The
/etc/stork/server.env
file contains the environment variables, butstork-server
does not automatically load them unless the--use-env-file
flag is set; the file must be loaded manually. The defaultsystemd
service unit is configured to load this file before starting the agent.
- Issue:
The server is running but rejects HTTP requests due to a TLS handshake error.
- Description:
HTTP requests sent via an Internet browser or tools like
curl
are rejected. The clients show a message similar to:OpenSSL SSL_write: Broken pipe, errno 32
. The Stork server logs contain aTLS handshake error
entry with thetls: client didn't provide a certificate
description.- Solution 1:
Leave the
STORK_REST_TLS_CA_CERTIFICATE
environment variable and the--rest-tls-ca
flag empty.- Solution 2:
Configure the Internet browser or HTTP tool to use a valid and trusted TLS client certificate. The client certificate must be signed by the authority whose CA certificate was provided in the server configuration.
- Explanation:
Providing the
STORK_REST_TLS_CA_CERTIFICATE
environment variable or the--rest-tls-ca
flag turns on TLS client certificate verification. HTTP requests must be assigned with a valid and trusted HTTP certificate, signed by the authority whose CA certificate was provided in the server configuration; otherwise, the request is rejected. This option improves server security by limiting access to only trusted users; it should not be used if there is no CA configured, or if it is desirable to allow login to the Stork server from any computer without prior setup.
- Issue:
The Stork server fails to start and returns the following error:
permission denied for schema public
.- Description:
A fresh installation of the Stork server is made and the database is empty. However, the Stork server does not start and the Stork tool returns an error on the database migration. The logs reveal denied access to the schema public.
- Solution 1:
Execute
GRANT ALL ON DATABASE stork_db TO stork_user;
on the Stork database (replacestork_db
andstork_user
with the proper names).- Solution 2:
Perform the migration using the Stork tool with the maintenance (e.g., super-admin) database credentials.
- Explanation:
In some Postgres installations (by default in Postgres 15 and above), the
CREATE
permission is only initially granted to the database owner. The Stork server needs this permission to perform the database migration on startup. This permission can be granted manually, or the Stork tool can be used to migrate the schema as the maintenance database user (e.g., super-admin).
- Issue:
The Stork server fails to start and returns the following error:
Cannot start the Stork Server: failed to load hooks from directory: '[HOOK DIRECTORY]': plugin.Open("[HOOK DIRECTORY]/[FILENAME]"): [HOOK DIRECTORY]/[FILENAME]: file too short
orCannot start the Stork Server: failed to load hooks from directory: '[HOOK DIRECTORY]': plugin.Open("[HOOK DIRECTORY]/[FILENAME]"): [HOOK DIRECTORY]/[FILENAME]: invalid ELF header
.- Solution:
Remove the given file from the hook directory.
- Explanation:
The file under the given path is not a valid Stork hook.
- Issue:
The Stork server fails to start and returns the following error:
Cannot start the Stork Server: incompatible hook version: 1.0.0
.- Solution:
Update the given hook.
- Explanation:
The hook is out-of-date and is incompatible with the Stork core application.
- Issue:
The Stork server fails to start and returns the following error:
Cannot start the Stork Server: plugin: symbol Version not found in plugin
.- Solution:
Remove or fix the given file.
- Explanation:
The hook directory contains the Go plugin but not the hook; the Go hook does not contain a required symbol.
- Issue:
The Stork server fails to start and returns the following error:
Cannot start the Stork Server: hook library dedicated for another program: Stork Agent
.- Solution:
Move the incompatible hooks to a separate directory.
- Explanation:
The Stork server requires the hook directory to contain only server hooks. The error message indicates that the hook directory contains hooks dedicated to the Stork agent.
- Issue:
The Stork server starts but the hooks are not loaded. The logs include the following message:
Cannot find plugin paths in: /usr/lib/stork-server/hooks: cannot list hook directory: /usr/lib/stork-server/hooks: open /usr/lib/stork-server/hooks: no such file or directory
.- Solution:
Create the hook directory or change the path in the configuration.
- Explanation:
The hook directory does not exist.
- Issue:
The Stork server fails to start and returns the following error:
Cannot start the Stork Server: open [HOOK DIRECTORY]: permission denied cannot list hook directory
.- Solution:
Grant read access to the hook directory to the
stork-server
user.- Explanation:
The hook directory is not readable.
- Issue:
The Stork server fails to start and returns the following error:
Cannot start the Stork Server: readdirent [HOOK DIRECTORY]/[FILENAME]: not a directory cannot list hook directory
.- Solution:
Change the hook directory path.
- Explanation:
A file was found instead of a directory under the given hook directory path.
5.3. High Virtual Memory Usage
Stork processes allocate a large amount of virtual memory, which is a common situation for applications written in Golang. The Go runtime uses virtual memory to manage memory efficiently. Virtual memory is not the same as physical memory. The size of the reserved virtual memory depends on the internal implementation details of the Go memory allocator. A high value of virtual memory usage is not alarming, as long as real memory usage is low.
Virtual and physical memory usage can be examined using the ps aux
command.
Virtual memory usage is displayed in the VSZ
column; the
RSS
column shows physical memory usage.
The usual virtual memory usage of the Stork agent on a machine with 16GB RAM, Go 1.22.4, and Ubuntu 22.04 is about 2.5-3GB. The real memory usage is relatively low, about 10-40MB for Kea deployments with dozens of subnets and host reservations and 40-80MB for deployments with thousands of subnets and host reservations.
References: