(I'm running on CentOS 5.8). I've been following the direction for a Clustered (Multiserver) Zookeeper Set-up, but getting an error when I try to start up my server. When I run the command as described in the documentation:
java -cp zookeeper-3.4.6.jar:lib/log4j-1.2.16.jar:conf \ org.apache.zookeeper.server.quorum.QuorumPeerMain conf/zoo.cfg
I get the error:
Error: Could not find or load main class org.apache.zookeeper.server.quorum.QuorumPeerMain
I have my files location as such and am running from the ~/zookeeper-3.4.6 directory:
~/zookeeper-3.4.6/zookeeper-3.4.6.jar
~/zookeeper-3.4.6/conf/zoo.cfg
~/zookeeper-3.4.6/data/myid
~/zookeeper-3.4.6/lib/log4j-1.2.16.jar
~/zookeeper-3.4.6/bin/zkServer.sh
Does anyone know why this error is happening? I don't quite understand the arguments that are being passed, so it is hard for me to debug the path issue. As a side note, I've tried running ./zookeeper-3.4.6/bin/zkServer.sh start, which did successfully work, but the documentation seems to indicate that command is meant for a single-node instance.
Edit:
I was able to make some progress by modifying the command and taking out the :conf \ part, so now I'm running:
java -cp zookeeper-3.4.6.jar:lib/log4j-1.2.16.jar: org.apache.zookeeper.server.quorum.QuorumPeerMain conf/zoo.cfg
I get a new error, but this is progress...
Exception in thread "main" java.lang.NoClassDefFoundError: org/slf4j/LoggerFacto
ry
at org.apache.zookeeper.server.quorum.QuorumPeerMain.<clinit>(QuorumPeer
Main.java:64)
Caused by: java.lang.ClassNotFoundException: org.slf4j.LoggerFactory
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 1 more
which corresponds to lines 63 and 64 from QuorumPeerMain
public class QuorumPeerMain {
private static final Logger LOG = LoggerFactory.getLogger(QuorumPeerMain.class);
I got the Error: Could not find or load main class org.apache.zookeeper.server.quorum.QuorumPeerMain, because I had downloaded the apache-zookeeper-X.X.X.tar.gz file and not the apache-zookeeper-X.X.X.bin.tar.gz file. Downloading, untarring and using the bin.tar file fixed it for me.
You can also build the binaries from the apache-zookeeper-X.X.X.tar.gz file; see the answer of #vincent.
This happens when you download and used apache-zookeeper-X.X.X.tar.gz, you should use apache-zookeeper-X.X.X-bin.tar.gz. this will surely solve this issue
The issue can be solved by untaring apache-zookeeper-3.5.6-bin.tar.gz. Initially, I encountered the same error while untared/installed apache-zookeeper-3.5.6.tar.gz and executed /bin/zkServer.sh start
Please make sure you have downloaded apache-zookeeper-3.5.6-bin.tar.gz
I got the same errors. I solved the error by check the README.md file in apache-zookeeper-[version].tar.gz Just type:
mvn clean install -DskipTests
then start the zookeeper. You will solve the error, too.
You should be able to run zkServer.sh to get a clustered setup. It will use the same conf/zoo.cfg that you are providing manually, which will contain the cluster endpoints.
The best way to check what you are missing from your classpath (and see the proper java command) is to run the zkServer.sh you said worked for you.
When it starts up, check the actual command used like this:
ps -ef | grep zookeeper
I also get this error when try to run Apache Zookeper v3.5.5 on Windows:
Error: Could not find or load main class org.apache.zookeeper.server.quorum.QuorumPeerMain
As said by #Onnonymous, I finish my problem by downloading the .bin.tar.gz (here) instead of .tar.gz version.
I am using apache-zookeeper-3.8.0-bin.tar.gz (Ubuntu 20.04)
This has all the necessary files to successfully start the zookeeper process.
specifying the other nodes in zoo.cfg file and starting the zookeeper automatically adds other nodes and starts the election process.
digital ocean has a good setup guide here setup zookeeper cluster
here's the zoo.cfg for reference
tickTime=2000
dataDir=/data/zookeeper
clientPort=2181
maxClientCnxns=60
initLimit=10
syncLimit=5
server.1=server1hostname/ip:2888:3888
server.2=server1hostname/ip:2888:3888
server.3=server1hostname/ip:2888:3888
Related
Every time i run Simple-example downloaded from github JavaLite examples, I get this error. Exception in thread "main" org.javalite.activejdbc.InitException: Failed to connect to JDBC URL: jdbc:mysql:mysql://localhost/movies with user: root. Also in read me file there is said to run mvn db-migrator:create command but I also get an error. Why is that, I have downloaded maven and my mvn process-classes builed successfully. Also I am interested in more JavaLite material, there are so few on the internet.
There is a README.md file in this example project:
https://github.com/javalite/javalite-examples/blob/master/simple-example/README.md
It has exact instructions to run this example. One of the steps is:
Adjust your database connection parameters in file:
src/main/resources/database.properties
This will ensure you have a correct configuration for your database.
I wrote a Singularity container that works just fine on my computer. However, when a colleague of mine tries to run it, he gets the error output
FATAL: container creation failed: failed to resolve session directory /usr/local/var/singularity/mnt/session: lstat /usr/local/var: no such file or directory
In the past, he could run containers I build. In fact, he used being able to run a container with the same recipe. The change was that the version of Singularity on the machine I use to build it was upgraded.
I entered the error in a search engine, and I only found a single hit, https://forum.image.sc/t/improving-cluster-supercomputer-performance-tesla-v100-volta-16-32gb-gpu/37459/8, in which this is not resolved.
Does anybody know a way to fix this? Or what the source of the problem is? Or a workaround, preferably one that does not require me to downgrade Singularity? (The machine on which I build it is shared between several users, that's why I don't want to do that.)
Okay, this was somewhat trivial to solve, we just had the colleague create the required folder,
mkdir -p /usr/local/var/singularity/mnt/{container,final,overlay,session}
I'm trying to get Scalding working on Zeppelin while using YARN. I followed the steps in the docs here to build the interpreter and set up the classpath override. When I run in local mode, code executes properly. However when I run on my cluster via YARN my jobs fail with:
Error: java.lang.ClassNotFoundException: cascading.CascadingException
or
Error: java.lang.ClassNotFoundException: cascading.tuple.TupleException
What is even stranger to me is that I can go into Zeppelin and execute:
import cascading.tuple.TupleException
import cascading.CascadingException
And both appear to have no problem finding those classes. It is only when I try to actually use scalding (on YARN), like loading data into a typed pipe and dumping that I get the ClassNotFoundException. Any ideas on how to debug or what to fix?
It looks like the cascading jars are not distributed to the YARN cluster. Please add "zeppelin/interpreter/scalding/*" to the args.string property of the scalding interpreter.
Here's the args.string we use:
-libjars /home/zeppelin-user/zeppelin/interpreter/scalding/,/home/zeppelin-user/deploy-bundle-201608111417/libs/ -Dscalding.reducer.estimator.classes=com.twitter.scalding.reducer_estimation.InputSizeReducerEstimator -Delephantbird.use.combine.input.format=true -Delephantbird.combine.split.size=134217728 --hdfs --repl
tmpjars contains jars that are distributed to the YARN cluster. You can see its contents with the command below:
%scalding
mode.asInstanceOf[Hdfs].conf.get("tmpjars").split(",").foreach(println)
Platform: TomEE Web profile 1.5.0.
I am trying to do a very basic thing, setup a data source for MySQL. I have read the official guide (http://openejb.apache.org/configuring-datasources.html). It asks us to enter a Resource element in openejb.xml. I can not find that file anywhere in tomee-webprofile-1.5.0. I read in other places that I could use tomee.xml for the same purpose. So, I added this to my conf/tomee.xml.
<Resource id="TestDS" type="DataSource">
JdbcDriver com.mysql.jdbc.Driver
JdbcUrl jdbc:mysql://localhost/test
UserName root
Password some_pass
</Resource>
I copied MySQL driver JAR to tomee/lib folder.
I wrote this code. Showing snippets here:
#Resource(name="TestDS")
DataSource ds;
Connection con = ds.getConnection();
PreparedStatement ps = con.prepareStatement("select * from UserProfile");
The prepareStatement() call is throwing this exception:
java.sql.SQLSyntaxErrorException: user lacks privilege or object not found: USERPROFILE
at org.hsqldb.jdbc.Util.sqlException(Unknown Source)
at org.hsqldb.jdbc.Util.sqlException(Unknown Source)
Why is the system using hsqldb driver? In fact, no matter what is use as name for #Resource, I get the same exception.
What am I doing wrong? I am starting TomEE from Eclipse, if that makes any difference.
I have tracked down the root cause. The problem happens only when I start TomEE from Eclipse. If I start it from command line, my data source definition works just fine.
It appears that when I run TomEE from command line, it uses configuration files from /.metadata/.plugins/org.eclipse.wst.server.core/tmp0/conf. To change this, I had to take these steps in Eclipse:
Remove all deployed projects from the server.
Open server settings and from "Server Locations" choose "Use Tomcat installation". This section is greyed out if you have at least one project still deployed to the server. So, make sure you have done step #1.
Restart the server and redeploy the application. Now, my application is finding the data source.
normally the installation is explained here http://tomee.apache.org/tomee-and-eclipse.html
[I would make this a comment to the answer of RajV, but do not have enough reputation to do so.]
Platform: Tomee 1.6.0 Webprofile, eclipse-jee-kepler-SR2-linux-gtk-x86_64 and OpenJDK 1.7.0_51
After doing the steps in http://tomee.apache.org/tomee-and-eclipse.html (including "Workspace Metadata Installation") I got the same error "user lacks privilege or object not found".
My reaction was to:
$ ln -s [workspace_path]/Servers/tomee.xml \
[workspace_path]/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/conf/
As an advantage of this solution TomEE in eclipse is always using the current version of Workspace/Servers/tomee.xml without any further manual operation.
For me, better solution is to put tomee.xml file in your wpt server directory (/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/conf) and define your datasource there.
I've followed the instructions in this URL: http://pmungai.wordpress.com/sakai-developer-guide/sakai-linux-cheatsheet/ and was able to compile and deploy sakai, however, after restarting tomcat, it will show me this:
root#ip-10-72-129-39:/opt/sakai# sh /opt/tomcat/bin/startup.sh
Using CATALINA_BASE: /opt/tomcat
Using CATALINA_HOME: /opt/tomcat
Using CATALINA_TMPDIR: /opt/tomcat/temp
Using JRE_HOME: /usr/lib/jvm/java-1.6.0-openjdk-amd64
Using CLASSPATH: /opt/tomcat/bin/bootstrap.jar
meaning that tomcat started successfully, but when I try to open the url from a browser, it simply loads forever, waiting for a response. If I try to shutdown tomcat, I get:
root#ip-10-72-129-39:/opt/sakai# sh /opt/tomcat/bin/shutdown.sh
Using CATALINA_BASE: /opt/tomcat
Using CATALINA_HOME: /opt/tomcat
Using CATALINA_TMPDIR: /opt/tomcat/temp
Using JRE_HOME: /usr/lib/jvm/java-1.6.0-openjdk-amd64
Using CLASSPATH: /opt/tomcat/bin/bootstrap.jar
2012-05-24 15:26:34,357 ERROR main org.apache.catalina.startup.Catalina - Catalina.stop:
java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:327)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:193)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:180)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:384)
at java.net.Socket.connect(Socket.java:546)
at java.net.Socket.connect(Socket.java:495)
at java.net.Socket.<init>(Socket.java:392)
at java.net.Socket.<init>(Socket.java:206)
at org.apache.catalina.startup.Catalina.stopServer(Catalina.java:395)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at org.apache.catalina.startup.Bootstrap.stopServer(Bootstrap.java:344)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:435)
Which happens when tomcat wasn't running to begin with.
I was able to test that tomcat was running exactly before deploying sakai, and right after, it wasn't able to load a web page.
Does anyone know what is going on?
Before starting a sakai development environment i'd sugges trying the sakai 2.8.x demo, it will provide an internal database and have some most of the standard functionalities.
You should download the demo project from:
https://testdrivesakai.com/portal
After you get used to the flows, configurations etc. you should set up your own instance with your own sakai schema. But when you do so also make sure you have at least some minimum hardware settings available and also the following tomcat startup arguments in place:
-Xms512m
-Xmx1024m
-XX:PermSize=128m
-XX:MaxPermSize=256m
-XX:NewSize=192m
-XX:MaxNewSize=384m
-Djava.awt.headless=true
-Dhttp.agent=Sakai
-Dorg.apache.jasper.compiler.Parser.STRICT_QUOTE_ESCAPING=false
-Dsun.lang.ClassLoader.allowArraySyntax=true
Also make sure you join the sakai-dev mailing list as you will get faster support by posting problems there.
The link to join the sakai dev-list:
http://collab.sakaiproject.org/mailman/listinfo/sakai-dev
In my experience this is usually database related. Are you using the out-of-the-box hsqldb or MySQL? After compiling and deploying with Maven into your tomcat directory when you first startup Tomcat it has to auto-create a bunch of tables. In many cases this can fail for a few reasons.
I will assume you are using MySQL as hsqldb has very few issues:
Sometimes the initial tomcat launch can shutdown your mysqlservice and not allow it to start back up again. This is usually due to it being unable to create error log files in the locations specified in your my.cnf file. Try commenting out any instances where these logs are being used and restart the service. Then retry the launch.
On Linux use "# ./catalina.sh run" instead of invoking the startup shell script. This will spawn a 2nd terminal window and show you everything that's happening (including any errors) while Tomcat is attempting to launch.
See if any tables were made in your database. If not then its a database connection issue. If so you should have around 377 tables or so depending on the Sakai version.
If you are getting "cache is not alive" errors in your tomcat logs this is a known race condition. You may need to disable the table auto-creation (assuming the tables have already been made from previous launch trials) and apply the patch outlined here:
KNL-1290
Without having error messages to work with it's difficult to diagnose your problem.