[FLINK-9103] SSL verification on TaskManager when parallelism > 1

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.4.0
• Fix Version/s: 1.4.3, 1.5.0
• Component/s: flink-docker, Runtime / Network
• Assignee: Edward Rojas
• Reporter: Edward Rojas
• Created: 28/Mar/18 15:15
• Updated: 28/Feb/19 11:31
• Resolved: 13/Apr/18 20:18

Description

In dynamic environments like Kubernetes, the SSL certificates can be generated to use only the DNS addresses for validation of the identity of servers, given that the IP can change eventually.

 

In this cases when executing Jobs with Parallelism set to 1, the SSL validations are good and the Jobmanager can communicate with Task manager and vice versa.

 

But with parallelism set to more than 1, SSL validation fails when Task Managers communicate to each other as it seems to try to validate against IP address:

Caused by: java.security.cert.CertificateException: No subject alternative names matching IP address 172.xx.xxx.xxx found 
at sun.security.util.HostnameChecker.matchIP(HostnameChecker.java:168) 
at sun.security.util.HostnameChecker.match(HostnameChecker.java:94) 
at sun.security.ssl.X509TrustManagerImpl.checkIdentity(X509TrustManagerImpl.java:455) 
at sun.security.ssl.X509TrustManagerImpl.checkIdentity(X509TrustManagerImpl.java:436) 
at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:252) 
at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:136) 
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1601) 
... 21 more 
 
From the logs, it seems the task managers register successfully its full address to Netty, but still the IP is used.
 
Attached pertinent logs from JobManager and a TaskManager. 

Issue Links

• links to: GitHub Pull Request #5789