Background: Firewall-Friendly Agents can be configured for server certificate authentication in the Axeda Builder project or via the Axeda Deployment Utility. When server certificate authentication is configured, the Agent will compare the certificate chain sent by the Platform to a local copy of the CA certificate chain stored in the SSLCACert.pem file in the Agent’s home directory.
The certificate validation compares three things:
- Does the name of the Platform certificate match the name in the request?
- Does the CA certificate match the CA certificate that signed the Platform certificate?
- Is the Platform or CA certificate not expired?
If the answer to any of these questions is “no”, then connection is refused and the Agent does not communicate further with the Platform. To determine if certificate trouble is an issue, see the Agent log: EKernel.log or xGate.log.
Recommendation: For Agent-Platform communications, we recommend always using SSL/HTTPS. If the Agent is not configured to validate the server certificate (via the trusted CA certificate), the system is vulnerable to a number of security attacks, including “man in the middle” attacks. This is critically important from a security perspective.
Note: For on-premise customers, if the Platform certificate needs to change, always update the SSLCACert.pem file on all Agents before updating the Platform certificate. (If the certificate is changed on the Platform before it is changed on the Agents, communications from the Agent will stop.)
Note: Axeda ODC automatically notifies on-demand customers about any certificate updates and renewals. At this point, though, Axeda ODC certificate updates are not scheduled for several years.
Finally, it is recommended that your Axeda Builder project always specify “Validate Server Certificate” and set the encryption level to the strongest level supported by the Web server. Axeda recommends 168 bit encryption, which will use one of the following encryption ciphers: AES256-SHA or DES-CBC3-SHA.
Need more information? For information about configuring and managing Agent certificate authentication, see Using SSL with Axeda® Platform Guide.
