# iNSTAL ON CENTOS **URL:** \ **Category:** Wowza Streaming Engine\ **Created:** [March 13, 2008, 8:59pm UTC](https://community.wowza.com/t/instal-on-centos/228 "2008-03-13T20:59:11Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![system](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/system/32/447_2.png) [@system](https://community.wowza.com/u/system)\ **Post date:** [March 13, 2008, 8:59pm UTC](https://community.wowza.com/t/instal-on-centos/228/1 "2008-03-13T20:59:11Z")
Hello, first the **JAVA install well on Fedora\_8.** An using **Centos\_5 and i install Java** ]# ./startup.sh Error parsing VHosts.xml (file:///usr/local/WowzaMediaServerPro/conf/VHosts.xml): java.lang.ClassCastException: java.util.ArrayList cannot be cast to org.w3c.dom.NodeList java.lang.ClassCastException: java.util.ArrayList cannot be cast to org.w3c.dom.NodeList at com.wowza.wms.bootstrap.Bootstrap.getServerInfo(Bootstrap.java:496) at com.wowza.wms.bootstrap.Bootstrap.startServer(Bootstrap.java:238) at com.wowza.wms.bootstrap.Bootstrap.main(Bootstrap.java:47) Exception in thread “main” java.lang.NoClassDefFoundError: com.wowza.wms.server.Server at java.lang.Class.initializeClass(libgcj.so.7rh) at java.lang.reflect.Method.invoke(libgcj.so.7rh) at com.wowza.wms.bootstrap.Bootstrap.startServer(Bootstrap.java:246) at com.wowza.wms.bootstrap.Bootstrap.main(Bootstrap.java:47) Caused by: java.lang.ClassNotFoundException: java.util.concurrent.Executor not found in java.net.URLClassLoader{urls=[file:/usr/local/WowzaMediaServerPro/lib/wms-core.jar,file:/usr/local/WowzaMediaServerPro/lib/log4j-1.2.14.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-bootstrap.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-mediareader-flv.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-ant.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-mediareader-mp3.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-server.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-jlayer.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-stream-record.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-mediawriter-flv.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-stream-live.jar,file:/usr/local/WowzaMediaServerPro/lib/jid3lib-0.5.4.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-commons-modeler.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-stream-shoutcast.jar,file:/usr/local/WowzaMediaServerPro/lib/wms-stream-file.jar], parent=gnu.gcj.runtime.SystemClassLoader{urls=[file:/usr/local/WowzaMediaServerPro/bin/wms-bootstrap.jar], parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}} at java.net.URLClassLoader.findClass(libgcj.so.7rh) at java.lang.ClassLoader.loadClass(libgcj.so.7rh) at java.lang.ClassLoader.loadClass(libgcj.so.7rh) at java.lang.Class.initializeClass(libgcj.so.7rh) …3 more **When I do this** ]# /usr/sbin/alternatives --config java There are 2 programs which provide ‘java’. Selection Command * * * - 1 /usr/lib/jvm/jre-1.4.2-gcj/bin/java - 2 /usr/java/jre1.6.0\_02/bin/java Enter to keep the current selection[+], or type selection number: 2 [root@ns6 bin]# java -version -bash: /usr/bin/java: No such file or directory [root@ns6 bin]# ./startup.sh ./startup.sh: line 24: java: command not found **But if I used 1 this got the old version** 1 /usr/lib/jvm/jre-1.4.2-gcj/bin/java \*+ 2 /usr/java/jre1.6.0\_02/bin/java Enter to keep the current selection[+], or type selection number: 1 [root@ns6 bin]# java -version java version “1.4.2” Any idea. ---
**Author:** ![Charlie\_Good](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/charlie_good/32/383_2.png) [@Charlie\_Good](https://community.wowza.com/u/Charlie_Good)\ **Post date:** [June 9, 2008, 5:01am UTC](https://community.wowza.com/t/instal-on-centos/228/2 "2008-06-09T05:01:43Z")
Many folks have had problems with virtual private servers and running Java applications. The virtualization system that runs many of these servers just can’t allocate a large enough contiguous block of memory to start Java applications. Charlie ---
**Author:** ![Charlie\_Good](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/charlie_good/32/383_2.png) [@Charlie\_Good](https://community.wowza.com/u/Charlie_Good)\ **Post date:** [June 9, 2008, 5:56pm UTC](https://community.wowza.com/t/instal-on-centos/228/3 "2008-06-09T17:56:31Z")
Excellent. Charlie ---
**Author:** ![J\_Cole](https://avatars.discourse-cdn.com/v4/letter/j/e56c9b/32.png) [@J\_Cole](https://community.wowza.com/u/J_Cole)\ **Post date:** [March 13, 2008, 9:33pm UTC](https://community.wowza.com/t/instal-on-centos/228/4 "2008-03-13T21:33:17Z")
Hello, I got the java to work [root@ns6 bin]# JAVA\_HOME=/usr/java/default; export JAVA\_HOME [root@ns6 bin]# PATH=$JAVA\_HOME/bin:$PATH; export PATH [root@ns6 bin]# java -version java version “1.6.0\_04” JC ---
**Author:** ![Charlie\_Good](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/charlie_good/32/383_2.png) [@Charlie\_Good](https://community.wowza.com/u/Charlie_Good)\ **Post date:** [June 9, 2008, 3:52am UTC](https://community.wowza.com/t/instal-on-centos/228/5 "2008-06-09T03:52:07Z")
How much memory is in the machine or is it a virtual private server? It sounds like the heap size is too large for your hardware. Try lowering the heap size defined in /usr/local/WowzaMediaServerPro/bin/setenv.sh: ```auto JAVA_OPTS="-Xmx250M" ``` Charlie ---
**Author:** ![Charlie\_Good](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/charlie_good/32/383_2.png) [@Charlie\_Good](https://community.wowza.com/u/Charlie_Good)\ **Post date:** [June 9, 2008, 4:21am UTC](https://community.wowza.com/t/instal-on-centos/228/6 "2008-06-09T04:21:05Z")
What do you get when you enter: ```auto java -version ``` You can try different VM sizes by entering: ```auto java -version -Xmx150M ``` Lower this number until it returns the version number. With 1GB of RAM you should be able to have a heap size of at least 250GB. What else do you have running on this machine? Is it a virtual private server? What is the OS, Java version, describe the hardware. Charlie ---
**Author:** ![Charlie\_Good](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/charlie_good/32/383_2.png) [@Charlie\_Good](https://community.wowza.com/u/Charlie_Good)\ **Post date:** [June 9, 2008, 7:55am UTC](https://community.wowza.com/t/instal-on-centos/228/7 "2008-06-09T07:55:41Z")
I am not sure about Windows VPS. I don’t know of any customers that are using Wowza Pro on a Windows VPS. The RAM upgrade will probably help. Charlie ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [June 9, 2008, 11:49am UTC](https://community.wowza.com/t/instal-on-centos/228/8 "2008-06-09T11:49:49Z")
How much memory is available on the machine you installed Wowza? Have you looked at these links?: General Tuning [https://www.wowza.com/docs/how-to-do-performance-tuning&highlight=java+version](https://www.wowza.com/docs/how-to-do-performance-tuning&highlight=java+version) More Tuning, Running the Server Java VM [http://community.wowza.com/t/-/41](http://community.wowza.com/t/-/41) (windows) [http://community.wowza.com/t/-/44](http://community.wowza.com/t/-/44) (linux) Richard ---
**Author:** ![rob\_sarroff](https://avatars.discourse-cdn.com/v4/letter/r/41988e/32.png) [@rob\_sarroff](https://community.wowza.com/u/rob_sarroff)\ **Post date:** [June 9, 2008, 11:41am UTC](https://community.wowza.com/t/instal-on-centos/228/9 "2008-06-09T11:41:42Z")
After completing the solution I get Error occurred during initialization of VM Could not reserve enough space for object heap Could not create the Java virtual machine any thoughts Thanks ---
**Author:** ![rob\_sarroff](https://avatars.discourse-cdn.com/v4/letter/r/41988e/32.png) [@rob\_sarroff](https://community.wowza.com/u/rob_sarroff)\ **Post date:** [June 9, 2008, 12:07pm UTC](https://community.wowza.com/t/instal-on-centos/228/10 "2008-06-09T12:07:38Z")
Thanks for the quick reply rrlanham. Oh!..it seems that I am only running 768M and I did know the min in 1GB. Short of adding more can it run with less than 1GB. …and Charlie I tried # JAVA\_OPTS=“Xmx250M” and still the same error. ---
**Author:** ![rob\_sarroff](https://avatars.discourse-cdn.com/v4/letter/r/41988e/32.png) [@rob\_sarroff](https://community.wowza.com/u/rob_sarroff)\ **Post date:** [June 9, 2008, 12:44pm UTC](https://community.wowza.com/t/instal-on-centos/228/11 "2008-06-09T12:44:27Z")
I’m running LINUX VPS Centos 5 32-bit jre1.5.0\_15 768M RAM **java -version** returns Error occurred during initialization of VM Could not reserve enough space for object heap Could not create the Java virtual machine **java -version -Xmx150M** returns same error java -version -Xmx50M returns same error ---
**Author:** ![rob\_sarroff](https://avatars.discourse-cdn.com/v4/letter/r/41988e/32.png) [@rob\_sarroff](https://community.wowza.com/u/rob_sarroff)\ **Post date:** [June 9, 2008, 1:07pm UTC](https://community.wowza.com/t/instal-on-centos/228/12 "2008-06-09T13:07:51Z")
I think I may have to go straight to Dedicated. I was hoping to do some testing before taking that leap. I will try and get a RAM upgrade. If I was to use a Windows VPS would it make any difference? Thanks Charlie. ---
**Author:** ![rob\_sarroff](https://avatars.discourse-cdn.com/v4/letter/r/41988e/32.png) [@rob\_sarroff](https://community.wowza.com/u/rob_sarroff)\ **Post date:** [June 10, 2008, 12:35am UTC](https://community.wowza.com/t/instal-on-centos/228/13 "2008-06-10T00:35:03Z")
Thanks for all the help. I just upgraded the guaranteed VPS RAM to 1024 it now works and streaming like a champion. Very happy. Cheers Rob