Configure custom SSL certificate for ActiveGate

Not for a Cluster ActiveGate

The following procedure—of directly uploading an SSL certificate to an ActiveGate—is not applicable for Cluster ActiveGates. Do not attempt to configure SSL certificates directly like this, on a Cluster ActiveGate. If you do this, the certificate will be overwritten by automatic management performed by Dynatrace.
For Cluster ActiveGates, you must upload your certificates using the Cluster Management Console or the Cluster REST API v1.

ActiveGate version 1.165 or later
Communication between OneAgents and ActiveGate takes place over an encrypted HTTPS channel. ActiveGate provides an authentication certificate to all connecting clients. While OneAgent instances may ignore the validity of ActiveGate certificates (depending on configuration), connections from browser clients (such as the RUM JavaScript tag) do verify that the hostname listed in the certificate is correct, before they send data.

ActiveGate can serve a custom certificate instead of the default one, on a per-environment basis. To configure this, you need a file in PKCS#12 format that contains a private key and its corresponding certificate chain.

Server Name Indication

To use Server Name Indication, include multiple certificates and keys in a single file.

Configure a custom certificate

To configure ActiveGate to use a custom certificate:

Copy the certificate file to the ssl directory.

File permissions

On Linux, make sure that permissions of the copied certificate file include the ActiveGate user you designated to run the ActiveGate service. If you didn't specify a custom user during installation, the default user is dtuserag.
On Windows, the ActiveGate service runs under the LocalService account.

Add the following entries to the custom.properties file in the ActiveGate configuration directory

[com.compuware.apm.webserver]
certificate-file = certificate-file.p12
certificate-password = password
certificate-alias = friendly-name

You need to add the above entries in the [com.compuware.apm.webserver] section. If there already is such a section in your custom.properties file, then just add the properties to the section. If the section doesn't exist, then create the section heading as well.

  • The certificate password, which you provide in the certificate-password property, will be obfuscated, following ActiveGate restart. The obfuscated password is stored in the certificate-password-encr property, while the original property is deleted.
  • If the certificate doesn't have a friendly name, you can omit the certificate-alias.

Known limitations

  • PEM file format isn't supported.
  • The password for the PKCS#12 file must be the same as the password for the key contained in this file.
    Don't use the -twopass option in the openssl pkcs12 command.
  • It's not possible to use multiple certificate files.

Managing certificates via REST API

ActiveGate version 1.167 or later

The certificates can be managed remotely via REST API. Prepare a PKCS#12 certificate file and you can upload it to ActiveGate using REST.

Authorization token

The API token is required for authorization. API tokens can be provided via HTTP headers or other means. See Dynatrace API - Tokens and authentication

API token used for the following actions must have ActiveGate certificate management permission.

Upload and activate certificate

The following REST point uploads and activates the selected certificate file. The password for the file must be the same as the password for the keys contained in the file, and they must be provided in an X-Password custom HTTP header.

curl https://{address of ActiveGate}:{port}/e/{environment ID}/api/v1/certificate/{certificate name to store} -H"Authorization: Api-Token {token}" -H"X-Password: {password}" -T {path to certificate file}

  • The port is configurable, 9999 by default.

  • The path to the certificate file can be just the name of a local file, or it can be a full path.

  • The name of the certificate, as given in the URL, does not have to match the name of the file.

For example:

curl https://myActiveGate:9999/e/myEnvironmentId/api/v1/certificate/cert.p12 -H"Authorization: Api-Token 123abc" -H"X-Password: myPassword" -T cert.p12

If the API call is successful, the HTTP response will be 200 with JSON-formatted description of the content of the activated certificate file.

If the API call fails, the HTTP response will be a 4xx or 5xx error code, with a plain text message.

Replace active certificate

You can't replace an active certificate using this endpoint. The operation will return HTTP 403 Forbidden. To replace an active certificate, upload a new certificate under a different name, then delete the old certificate.

Delete certificate

Deletes the selected certificate on ActiveGate.

curl -XDELETE https://myActiveGate:9999/e/myEnvironmentId/api/v1/certificate/cert.p12 -H"Authorization: Api-Token 123abc"

If the certificate is deleted successfully, the API call will respond with HTTP 200 code with no content.

If the file with the specified name does not exist, the API call will respond with HTTP 404 Not found code.

If the certificate file is currently in use, the API call will respond with HTTP 403 Forbidden code.

Activate certificate

Activates an existing previously-uploaded certificate file using the specified password.

curl -XPOST https://myActiveGate:9999/e/myEnvironmentId/api/v1/certificate/cert.p12/activate -H"Authorization: Api-Token 123abc" -d"{\"password\":\"pass\"}"
curl -XPOST https://myActiveGate:9999/e/myEnvironmentId/api/v1/certificate/cert.p12/activate -H"Authorization: Api-Token 123abc" -H"X-Password: pass"

If the certificate is successfully activated, the API call will respond with HTTP 200 code, with JSON-formatted description of the content of the activated certificate file.

If the requested certificate file does not exist on the ActiveGate, the API call will respond with HTTP 404 code.

If the provided password does not match, the API call responds with HTTP 400 code.

List all certificates

Returns a JSON-formatted list of all uploaded files.

curl https://myActiveGate:9999/e/myEnvironmentId/api/v1/certificate/list -H"Authorization: Api-Token 123abc"

If the active keystore is on the list, its entry will contain additional details.

Example response:

[
   {
      "name":"cert_demo.p12"
   
},
   {      "name":"cert.p12",
      "desc":[         {
            "alias":"local",
            "description":"Subject:CN=myActiveGate;Valid from:Fri Feb 15 13:16:58 CET 2019;Valid to:Sat Feb 15 13:16:58 CET 2020;Serial number:71d275dd3983c3cb9382437275dd3983c3cb93dbca"
         
},
         {
            "alias":"dynatrace",
            "description":"Subject:CN=*.clients.dynatrace.org;Valid from:Thu Feb 21 10:06:03 CET 2019;Valid to:Fri Feb 21 10:06:03 CET 2020;Serial number:6dc7008ab269ecebeed03652ce08ab269ecebeeeb33"
         
}
      
]
   
},
   {
      "name":"cert_key_1.p12"
   
}
]

Describe certificate

This API call returns a JSON-formatted description of the selected file.

curl https://myActiveGate:9999/e/myEnvironmentId/api/v1/certificate/cert.p12/list -H"Authorization: Api-Token 123abc" -H"X-Password: pass"
curl -XPOST https://myActiveGate:9999/e/myEnvironmentId/api/v1/certificate/cert.p12/list -H"Authorization: Api-Token 123abc" -H"X-Password: pass"
curl -XPOST https://myActiveGate:9999/e/myEnvironmentId/api/v1/certificate/cert.p12/list -H"Authorization: Api-Token 123abc" -d"{\"password\":\"pass\"}"

If the requested certificate file does not exist on the ActiveGate, the API call will respond with HTTP 404 code.

If the password doesn't match, the API call responds with HTTP 400 code.

Example response:

{   "name":"cert.p12",
   "desc":[      {
         "alias":"local",
         "description":"Subject:CN=myActiveGate;Valid from:Fri Feb 15 13:16:58 CET 2019;Valid to:Sat Feb 15 13:16:58 CET 2020;Serial number:7137275dd398c4182437275dd3983c3cb93dbca"
      
},
      {
         "alias":"dynatrace",
         "description":"Subject:CN=*.clients.dynatrace.org;Valid from:Thu Feb 21 10:06:03 CET 2019;Valid to:Fri Feb 21 10:06:03 CET 2020;Serial number:6d2ce08ab269ecebeee7f1bd03652ce08ab269ecebeeeb33"
      
}
   
]
}

Troubleshooting

When the certificate file and password are specified, ActiveGate tries to use the defined configuration.

  • If either the file or the password is missing, ActiveGate will silently fall back to the default configuration. The log entry in both cases is the same.

  • If ActiveGate tries to use the configured certificate and determines that the configuration is unusable, it will use the default SSL certificate and it will write the following log entry:

UTC WARNING [<1>] [CollectorImpl] Unusable custom SSL config, falling back to default.

ActiveGate additionally logs the reason why it couldn't use the configured certificate. For example, if the alias doesn't match the file contents, ActiveGate will write an entry in the log file:

UTC SEVERE [<1>] [SSLEnvironment] missing configured-alias entry in keystore:/var/lib/dynatrace/gateway/config/../ssl/cert-file.p12, available aliases: available-alias,

Create a certificate file for testing

To create a self-signed PKCS#12 certificate file for testing

Generate a key and a self-signed certificate:

openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365 -subj "/CN=localhost"

Convert the generated files to PKCS#12 format:

openssl pkcs12 -export -inkey key.pem -in cert.pem -out cert_key.p12

or, to set a friendly name, use:

openssl pkcs12 -export -inkey key.pem -in cert.pem -out cert_key.p12 -name friendly-name