@AppaRao,
Thanks for bringing this up. In the future, it would be a good idea to create a new thread rather than continue on an older one like this. When that initial message was posted, I think Cloudera Manager's agent was not able to use anything but TLSv1 (which has since been fixed).
Cloudera is working on documenting this information. For now, I'll add in what we have.
NOTE:
- You must have CDH 5.13.1 or higher in order for these steps to work for you
- We have only tested so far on Redhat and CentOS 6 and 7
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Java Based Components
The vast majority of the components in the ecosystem are written in Java. This includes Accumulo, Flume, HBase, HDFS, Hive, Kafka, the Keystore Indexer, MapReduce, Oozie, Sentry, Solr, Spark, Sqoop, Yarn, and ZooKeeper. What you need to do is to disable the ciphers on Java which then applied to most of the Java-based services once they are restarted.
Fortunately, there is one universal place to enforce TLS usage for all Java-based components. This is the "java.security" file.
Step 1: Update java.security
- Open $JAVA_HOME/jre/lib/security/java.security in an editor
- Add or replace this line:
jdk.tls.disabledAlgorithms=SSLv3, TLSv1, TLSv1.1, RC4, MD5withRSA, DH keySize < 768, 3DES_EDE_CBC
NOTE:
- This must be done on every machine in the cluster. Whenever Java is upgraded, this step must be performed again.
HUE
The components of interest in Hue are the Hue load balancer and the Hue servers. We recommend the use of the Hue load balancer because more cipher suites will be available, and there is no issue with Firefox (as described below).
This first change is to the Hue load balancer.
Step 2: The Hue load balancer
On the CM machine, edit /usr/share/cmf/hue/httpd/httpd.conf
Edit the SSLProtocol line to look like this:
SSLProtocol -all +TLSv1.2
NOTE: This step also has to be performed after each CM upgrade.
Step 3: The Hue Server
In CM, add the following to the “Hue Service Advanced Configuration Snippet (Safety Valve) for hue_safety_valve.ini”
[desktop]
ssl_cipher_list=DEFAULT:!aNULL:!eNULL:!LOW:!EXPORT:!SSLv2:!SSLv3:!TLSv1
NOTE: The Firefox web browser does not support any cipher suites that overlap with these ciphers. As a result, the Firefox web browser will not load the page and will display the error “SSL_ERROR_NO_CYPHER_OVERLAP”. Chrome, IE, Edge, and Safari do not have this issue, and are fine. This issue does not exist for the Hue Load Balancer above.
Impala
There are two different mechanisms to get TLS 1.2 support, depending on your operating system. On RHEL/CentOS 7, add the following to a CM Configuration Snippet (Safety Valve).
Step 4a: Impala on RHEL/CentOS 7
In CM, add the following parameter in Impala's safety valve: Impala Command Line Argument Advanced Configuration Snippet (Safety Valve)
-ssl_minimum_version=tlsv1.2
On RHEL/CentOS 6, the above flag unfortunately does not work. Add the following instead:
Step 4b: Impala on RHEL/CentOS 6
In CM, add the following parameter in Impala's safety valve: Impala Command Line Argument Advanced Configuration Snippet (Safety Valve)
-ssl_cipher_list=DEFAULT:!aNULL:!eNULL:!LOW:!EXPORT:!SSLv2:!SSLv3:!TLS1
NOTE: This solution has the same caveats with respect to Firefox as described above for Hue.
Kudu
There are two ports to configure for Kudu, the rpc protocol port and the webserver protocol port. In CDH 5.13.1 it’s possible to restrict the TLS protocol to TLS 1.2 for the rpc protocol port. This is the port where that all the data travels through. Unfortunately it’s not possible to similarly enforce TLS 1.2 on the web server port in CDH 5.13.1. The traffic that goes over the web server port is of a generally non-sensitive nature - like status.
Like Impala, there are two different solutions depending on the OS version. For RHEL/CentOS 7, do this:
Step 5a: Kudu on RHEL/CentOS 7
In CM, add the following parameter to the “Kudu Service Advanced Configuration Snippet (Safety Valve) for gflagfile”
-rpc_tls_min_protocol=TLSv1.2
On RHEL/CentOS 6, add the following instead:
Step 5b: Kudu on RHEL/CentOS 6
In CM, add the following parameter to the “Kudu Service Advanced Configuration Snippet (Safety Valve) for gflagfile”
-rpc_tls_ciphers=DEFAULT:!aNULL:!eNULL:!LOW:!EXPORT:!SSLv2:!SSLv3:!TLSv1
NOTE: Once again, this solution for RHEL/CentOS 6 has the same caveats with respect to Firefox as described above for Hue.
Restart
Now you’ll want to restart everything.
Step 6: Restart
- In CM, restart all the affected clusters
- In CM, restart the Cloudera Management Services
- On the CM server machine, restart CM itself using
sudo service cloudera-scm-server restart
