we are currently running Apache Cassandra 1.2.13 on 4 machines having Java 6 and are planning to upgrade Java to version 7.
Is it possible to do a rolling Java upgrade in a running cluster, i.e. node by node?
I know that Thrift protocols for client-server communication are incompatible for Java versions 6 & 7. How does that apply to the internal server-server communication within a cluster?
I haven't found any mentioning about that in the documentation or other sources.
Related
We deploy standalone ES pods and I saw that the system requirements say that Java 17 or higher is to be used. The java applications (separate pods of course) depending on ES are still on java 8 and we have no intention of upgrading the java version anytime soon. I wanted to confirm with the community at large if they faced issues any issues calling ES from applications on java 8? We are using the standard ES java libraries
org.elasticsearch.client:elasticsearch-rest-client
org.elasticsearch.plugin:parent-join-client
org.elasticsearch:elasticsearch-core
org.elasticsearch:elasticsearch
org.elasticsearch.client:elasticsearch-rest-high-level-client
I know restHighLevelClient is deprecated but we depend on spring-data-elasticsearch to provide some of the integration support.
I don't have enough reputation to add comment. I have similar problem on the upgrade. Here is from readme https://github.com/spring-projects/spring-data-elasticsearch
In Elasticsearch 8, the RestHighLevelCLient has been removed. This means that a switch to this client version can only be done with the next major upgrade which will be Spring Data Elasticsearch 5, based on Spring Data 3, used by Spring Boot 3, based on Spring 6 and Java 17.
Below has dependencies and upgrade info.
https://www.elastic.co/guide/en/elasticsearch/reference/current/dependencies-versions.html
https://www.elastic.co/guide/en/elasticsearch/reference/current/setup-upgrade.html
I am using java 6 with GWT2.2.1, but the current requirement is to upgrade java from java 6 to Java 7. Is it possible to upgrade?
Your help will be appreciated.
Java 7 support was added in GWT 2.6.0. On the server side, you can use whatever Java version you like. However on the client side, you won't be able to use Java 7 features with GWT <2.6.0. You can use a Java 7 (or even 8) JDK to compile your project, just force it to use Java 6 (and of course, don't use features from Java >6 in your client side code), for example, using -sourceLevel 6.
At the moment, we have both our Hadoop cluster (CDH 4.1.2) and services that communicate with it via hadoop-client running Java 6. We're planning to move those client components to Java 8 leaving Hadoop servers running on top of Java 6 as they do now because Cloudera has declared support for JDK 8 only since version 5.3.0, and we're not planning to upgrade Hadoop - details here:
https://www.cloudera.com/content/cloudera/en/documentation/core/latest/topics/cdh_rn_new_in_530.html
Therefore, our concern is whether different versions of Java in cluster (6) and in client components (8) may lead to problems of any kind. Internet hasn't been of big help as long as Hadoop compatibility with Java is mainly discussed regarding migration of server components, so please share your experience relevant to this matter if you have one.
Attempting to move over an older web app from Java 6 to Java 7, if the application and container stay the same, can some EhCache cluster nodes be on JDK 7 (or 8) and other remain on JDK 6 without any compatibility issues?
You should not have any problem with this. Serialization is stable across JVM versions.
I am using Jboss 2.4.11, if i upgrade JDK from 1.4 to 6 How is the jboss server going to handle the application?. What are the common things i should start investigating while i am in the process of the upgrade. I am looking at the Oracle's documentation and other posts in stackoverflow related to jdk 6 backwards compatibility with v1.4. My question is more specific towards using Jboss server. Also the application uses ejb 1.1
I'd recomment to move from one consistent system to another one. Even JBoss 4 needs a special version for JDK1.6. Java 5 brought MBeans rigth into the VM and older versions of JBoss used MBeans for configuration. As there must not be to MBean servers within a single VM this was a big issue, when migrated to java5. As EJB 1.1 is still supported I'd recomment to move at least to JBoss 4.2 as this is still kind of similar to older versions, while JBoss 7 is totally different.
The only thing that will really help you to get the migration a little bit smother are tests. At least quite a number of integration tests.