http://www.datastax.com/support-forums/tags/opscenter Software, Support, and Training for Apache Cassandra en-US Wed, 19 Jun 2013 10:36:54 +0000 http://bbpress.org/?v=1.0.3 q http://www.datastax.com/support-forums/search.php http://www.datastax.com/support-forums/topic/multiple-opscenter-agents#post-6340 Fri, 07 Sep 2012 17:40:29 +0000 thobbs 6340@http://www.datastax.com/support-forums/ <p>Perhaps the most important thing is to use dedicated disks for each Cassandra node, if possible. I don't think there are many best practices that apply to virtualized environments in general beyond that.</p> <p>For benchmarking, I suggest using the cassandra-stress tool that comes with Cassandra packages. </p> http://www.datastax.com/support-forums/topic/multiple-opscenter-agents#post-6334 Fri, 07 Sep 2012 14:28:46 +0000 schalla 6334@http://www.datastax.com/support-forums/ <p>Thank you Nick. Are there any best practices/benchmarks that you can point on running Cassandra in a virtualized environment? </p> http://www.datastax.com/support-forums/topic/opscenter-141-problem-on-mac-os-1073-importerror-no-module-named-twistedscriptstwistd#post-3431 Mon, 23 Jul 2012 02:38:31 +0000 thobbs 3431@http://www.datastax.com/support-forums/ <p>lotka,</p> <p>Fedora isn't a supported distro for OpsCenter at this time. It's <em>possible</em> that it will run on Fedora with some modification, but I have no idea if it actually will.</p> <p>If you want to try, edit bin/opscenter and replace the line</p> <p><code>PY_DISTRO=&quot;./lib/py-redhat/${PY_VER}/shared/${PY_ARCH}:./lib/py-redhat/${PY_VER}/${VER}/${PY_ARCH}&quot;</code></p> <p>with</p> <p><code>PY_DISTRO=&quot;./lib/py-redhat/2.7/shared/amd64:./lib/py-redhat/2.7/6/amd64&quot;</code></p> <p>That assumes you're using a 64 bit system. If not, replace amd64 with i386. Hopefully that might work, but if not, there's not much else we can do. </p> http://www.datastax.com/support-forums/topic/opscenter-141-problem-on-mac-os-1073-importerror-no-module-named-twistedscriptstwistd#post-3330 Fri, 20 Jul 2012 13:55:27 +0000 lotka 3330@http://www.datastax.com/support-forums/ <p>Hi,<br /> I am replaying to this post because I cannot open a new one (how is this possible?)<br /> I have the same problem to run opscenter 2.1 on Fedora 16.<br /> I don't have root priviliges so I downloaded tarball. But I've got the same exception. I've Python 2.7 installed.<br /> And in my configuration I have this line<br /> <code>+PY_VER=$($PYTHON -c &quot;import platform; v = platform.python_version(); print v[:v.index(&#039;.&#039;, 2)]&quot;)</code><br /> instead of this one:<br /> <code>-PY_VER=$($PYTHON -c &quot;import sys; v = sys.version; print v[:v.index(&#039;.&#039;, 2)]&quot;)</code><br /> (probably its becouse the fix that you mentioned.<br /> Any clues? </p> http://www.datastax.com/support-forums/topic/opscenter#post-3158 Tue, 17 Jul 2012 04:58:06 +0000 nickmbailey 3158@http://www.datastax.com/support-forums/ <p>Abhijit,</p> <p>By default the opscenter web server binds to 127.0.0.1. None of the connections listed there are the opscenter process. You can change the interface the web server binds to in the opscenterd.conf file.</p> <p><a href="http://www.datastax.com/docs/opscenter/configure/configure_opscenter_adv" rel="nofollow">http://www.datastax.com/docs/opscenter/configure/configure_opscenter_adv</a> </p> http://www.datastax.com/support-forums/topic/opscenter#post-3125 Mon, 16 Jul 2012 11:12:00 +0000 Abhijit 3125@http://www.datastax.com/support-forums/ <p>Hi,<br /> I have SSL installed in my machine as well as rest of all the settings are up to mark. But still i am not able to access the web browser. What else may be the reason?<br /> This is the netstat report<br /> Active Internet connections (servers and established)<br /> Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name<br /> tcp 0 0 192.168.2.212:22 192.168.2.210:41914 ESTABLISHED 1393/sshd: abhi [pr<br /> tcp 1 0 192.168.2.212:9160 192.168.2.210:49450 CLOSE_WAIT 1845/java<br /> tcp 0 0 192.168.2.212:22 192.168.2.210:41920 ESTABLISHED 1983/sshd: abhi [pr<br /> tcp 0 0 192.168.2.212:9160 192.168.2.212:46289 ESTABLISHED 1845/java<br /> tcp 5 0 192.168.2.212:9160 192.168.2.210:49426 CLOSE_WAIT 1845/java<br /> tcp 0 0 192.168.2.212:9160 192.168.2.210:49428 ESTABLISHED 1845/java<br /> tcp 5 0 192.168.2.212:9160 192.168.2.210:49453 CLOSE_WAIT 1845/java<br /> tcp 1 0 192.168.2.212:40647 91.189.89.144:80 CLOSE_WAIT 1364/ubuntu-geoip-p<br /> tcp 5 0 192.168.2.212:9160 192.168.2.210:49807 CLOSE_WAIT 1845/java<br /> tcp 0 0 192.168.2.212:46289 192.168.2.212:9160 ESTABLISHED 2543/python<br /> tcp 5 0 192.168.2.212:9160 192.168.2.210:49822 CLOSE_WAIT 1845/java<br /> tcp 0 0 192.168.2.212:22 192.168.2.210:42672 ESTABLISHED 3619/sshd: abhi [pr<br /> tcp6 0 0 :::22 :::* LISTEN 445/sshd </p> http://www.datastax.com/support-forums/topic/multiple-opscenter-agents#post-2756 Fri, 06 Jul 2012 16:48:44 +0000 nickmbailey 2756@http://www.datastax.com/support-forums/ <p>Schalla,</p> <p>First I will note that running multiple cassandra servers on a single host is not recommended. If it is necessary it is often easier to use virtualization to simulate multiple servers. What you are looking to do is possible though.</p> <p>You will need to run multiple agents on the Cassandra servers, yes. You can install multiple agents when using the manual agent installation. You should follow the process described here:</p> <p><a href="http://www.datastax.com/docs/opscenter/agent/agent_tar" rel="nofollow">http://www.datastax.com/docs/opscenter/agent/agent_tar</a></p> <p>You will need to install each agent to a different location on the machine. You will also need to make a manual change to the conf/address.yaml file. You should add the following lines to each file:</p> <p>local_interface: &lt;listen_address&gt;<br /> jmx_port: &lt;port&gt;</p> <p>The &lt;listen_address&gt; above should be replaced with the configured listen_address from your cassandra.yaml depending on which cassandra instance the agent should monitor. Additionally each cassandra will need to use a different jmx port in order to run on the same host. You should use the correct port accordingly.</p> <p>-Nick </p> http://www.datastax.com/support-forums/topic/multiple-opscenter-agents#post-2641 Tue, 03 Jul 2012 16:52:26 +0000 schalla 2641@http://www.datastax.com/support-forums/ <p>I have two servers (ServerX and ServerY). I need to run multiple Cassandra instances on a given server (say Serverx). Do I need to run multiple OpsCenter agents to collect data on each Cassandra node? If so please point me to the documentation for OpsCenter server/agent. Here is the environment detail.</p> <p>RHEL 5.8<br /> OpsCenter 2.1 </p> http://www.datastax.com/support-forums/topic/unable-to-install-remote-agent-couldnt-get-fingerprint-for-ssh-key#post-1946 Sun, 20 May 2012 20:25:21 +0000 nickmbailey 1946@http://www.datastax.com/support-forums/ <p>Glad you got everything working. I've created an internal bug to investigate SELinux on RHEL 6.0 further. If we need any further information we will update this forum post.</p> <p>Thanks for the bug report! </p> http://www.datastax.com/support-forums/topic/unable-to-install-remote-agent-couldnt-get-fingerprint-for-ssh-key#post-1945 Sat, 19 May 2012 16:53:31 +0000 Anonymous 1945@http://www.datastax.com/support-forums/ <p>I've been able to resolve the problem, and now all agents are working - thanks for your help. The situation was that I'd disabled SSL while working on an earlier agent connection problem. Uninstalling and reinstalling the agent restored the default SSL settings, leaving the agent trying to use SSL to connect to an opscenter that was not using it.</p> <p>I appreciate very much your prompt and helpful responses. Your suggested workaround of disabling SELinux during the agent install was the key to resolution. I'm a little concerned that this was necessary, and if you need anything more to diagnose it, I'll be happy to provide it. However, my original issue is resolved. </p> http://www.datastax.com/support-forums/topic/unable-to-install-remote-agent-couldnt-get-fingerprint-for-ssh-key#post-1943 Sat, 19 May 2012 01:05:32 +0000 nickmbailey 1943@http://www.datastax.com/support-forums/ <p>Thanks for the additional information. </p> <p>Regarding the install from the UI not working, do you know if the agent process managed to start? There are two places I would look for errors. '/var/log/opscenter-agent/installer.log' will contain the log of the installation process. If that appears normal then the normal agent log '/var/log/opscenter-agent/agent.log' should hopefully indicate any communication problems if the install succeeded and the process started.</p> <p>Any errors from those logs will help us debug, but obviously if the manual installation is working for you, you can continue to use that. </p> http://www.datastax.com/support-forums/topic/unable-to-install-remote-agent-couldnt-get-fingerprint-for-ssh-key#post-1942 Sat, 19 May 2012 00:57:17 +0000 Anonymous 1942@http://www.datastax.com/support-forums/ <p>I had already installed the agent manually, but uninstalled it with </p> <blockquote><p>yum opscenter-agent erase</p></blockquote> <p>and cycled opscenter.</p> <p>This restored the problem. Here is additional context from the failed install:</p> <blockquote><p> 2012-05-18 17:42:47-0700 [CA_APM] INFO: Beginning install of OpsCenter agent to 138.42.81.221<br /> 2012-05-18 17:42:47-0700 [] couldn't get fingerprint for SSH key ('ssh-rsa', 'AAAAB3NzaC1yc2EAAAABIwAAAQEA3TgMr2NFv5HI5m++1ycFrJE75h6NPRW/Bg+RoMTF68jhgbr8TBRpO43gntPc5WA+CyTEV3Jj9P+xfMVccP2q/+uqHYqZU3fYxFn3Dm2WpuZh0Q8E3v7yNOolsOUarc0pZ6iFeQnaOcIv7lc9xNFURsDkcJgACejnPN9YRvozCdWw0HyzkDDLuO2HAlpySSeSk1y1mj5PEctyvMQ7o+3SIIueykiUcqelCMDFEFMvZENtWkb6TbsytTFjLg6GoWFUgImUFrrT390svSx0inz1OVl9LNpx6C0SZAuCD+FD8y7Yw6puE3TCneaP2hh3N4W6c6XTlkICqnLWZ7wTNbkxrw=='):</p> <p> /usr/share/opscenter/tmp/tmp0tSgtF: Permission denied<br /> Traceback (most recent call last):<br /> Failure: twisted.internet.error.ProcessTerminated: A process has ended with a probable error condition: process ended with exit code 1. </p></blockquote> <p>I then tried your suggested workaround, and it appeared to work - the agent install finished successfully.</p> <blockquote><p> 2012-05-18 17:47:01-0700 [CA_APM] INFO: Beginning install of OpsCenter agent to 138.42.81.221<br /> 2012-05-18 17:47:32-0700 [CA_APM] INFO: Install of OpsCenter agent to 138.42.81.221 complete </p></blockquote> <p>However, opscenter didn't detect the agent, even after a recycle. I tried - and succeeded - in installing it a second time, and also recycled opscenter. It still cannot detect the agent (the opscenter console still states "1 of 2 agents connected" and shows a "Fix" link. The missing agent is on the opscenter server box itself. </p> http://www.datastax.com/support-forums/topic/unable-to-install-remote-agent-couldnt-get-fingerprint-for-ssh-key#post-1941 Fri, 18 May 2012 17:59:27 +0000 nickmbailey 1941@http://www.datastax.com/support-forums/ <p>Have you tried installing the agents again since running the chcon command? Assuming it is still failing, attaching more context from the failure in the log may help.</p> <p>As a temporary workaround I believe you can disable selinux temporarily in order to install the agents. 'setenforce 0' should accomplish this. You may also need to restart the OpsCenter process. </p> http://www.datastax.com/support-forums/topic/unable-to-install-remote-agent-couldnt-get-fingerprint-for-ssh-key#post-1932 Fri, 18 May 2012 00:18:28 +0000 Anonymous 1932@http://www.datastax.com/support-forums/ <p>SELinux is enabled. The chcon command you suggested gave no response, so I added the -v argument:</p> <blockquote><p> [root@bvdl-vm-01 cassandra]# sestatus<br /> SELinux status: enabled<br /> SELinuxfs mount: /selinux<br /> Current mode: enforcing<br /> Mode from config file: enforcing<br /> Policy version: 24<br /> Policy from config file: targeted<br /> [root@bvdl-vm-01 cassandra]# which chcon<br /> /usr/bin/chcon<br /> [root@bvdl-vm-01 cassandra]# which setenforce<br /> /usr/sbin/setenforce<br /> [root@bvdl-vm-01 cassandra]# chcon -vt ssh_home_t /usr/share/opscenter/tmp<br /> changing security context of `/usr/share/opscenter/tmp' </p></blockquote> http://www.datastax.com/support-forums/topic/unable-to-install-remote-agent-couldnt-get-fingerprint-for-ssh-key#post-1930 Thu, 17 May 2012 01:30:47 +0000 nickmbailey 1930@http://www.datastax.com/support-forums/ <p>This also sounds like a problem with SELinux in RHEL 6.0. Can you confirm if SELinux is enabled or not?</p> <p>Assuming it is running can you run the following commands and post the output:</p> <p>which chcon<br /> which setenforce<br /> chcon -t ssh_home_t /usr/share/opscenter/tmp</p> <p>That last command is the command that should have been run during install to enable the correct SELinux permissions on the directory. The first two commands will help us debug why it may not have worked. </p>