Question: When I try to do certain operation from Nagios UI, I get “Error: Could not open command file ‘/usr/local/nagios/var/rw/nagios.cmd’ for update!” error. How do I fix this?
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Oracle VM Manager is required to manage one or more Oracle VM Server. This tutorial, explains high-level steps on how to install and configure Oracle VM Manager. In this example, I’ve used the current stable version of OVM 3.2.2. But, the steps are pretty similar for other OVM versions.
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Question: I installed Nagios Core, and when I go to Nagios UI, I see the home page. But clicking on any of the menu links gives “Internal Server Error” message in the browser. However Apache error_log has “(13)Permission denied: exec of ‘/usr/local/nagios/sbin/status.cgi’ failed” error message. How can I fix this?
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ssh-add is a helper program for ssh-agent.

ssh-add adds RSA or DSA identity files to the ssh agent. For ssh-add to work properly, the agent should be running, and have the SSH_AUTH_SOCK environment variable set.
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rpc.mountd is the server daemon for the NFS mount.

When a remote NFS client is trying to access a file system on the NFS server where mountd is running, this daemon will check the access control in the export table to determine whether to give access to the remote NFS client or not.

rpc.mountd is part of nfs-utils package. You should install it if you don’t have it, using yum install nfs-utils.
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stty command is used to manipulate the terminal settings. You can view and modify the terminal settings using this command as explained below.
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sshd is OpenSSHD Daemon. When sshd receives a request for connection from a client, it creates a new process for that particular connection. You can use either password or key exchange authentication (there are others types too).

Typically this daemon gets the configuration parameters from the /etc/ssh/sshd_config file. But, you can also specify the options from the command line, in which case, it overrides the parameters from the sshd_config file.
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xinetd stands for extended Internet services daemon. This is a replacement for inetd. xinetd starts and listens on all the service ports that you’ve defined, and when there is an incoming request to a particular port that it is listening to, it starts the corresponding service.
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uuencode command is used to encode a binary file as explained in the examples below.
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uudecode command is used to decode the ASCII representation that was created by the uuencode command. Please note that uuencode command encodes a binary file to ASCII text.
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