Nagios Notifications Not Working

If for some reason, your Nagios server stops sending out host alerts it’s more than likely that recent update broke it. If that is the case, you will need to re-run the update, which should fix the issue. In the event that this does not fix the problem, check your email settings in nagios. This […]

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XINETD/NRPE | Cannot Write to Pidfile

 Cannot write to pidfile ‘/var/run/nagios/’ – check your privileges. This error occurs when the “pidfile” cannot be rewritten. In most cases, this happens after a reboot and the file itself is read-only instead of read/write. If that is the case, go ahead and restart the xinetd and nrpe services. service xinetd restart service nrpe restart Next, check the status […]

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Install VNC-Server on CentOS 7

First, i logged into my server as root, to make things a little easier. I would recommend doing the same thing to help speed up the processes. After I logged into the system, I installed VNC-server.  yum install tigervnc-server Once all the packages were installed, go ahead and run an update. yum -y update && […]

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Enable noop IO scheduler

Noop Scheduler, for those of you who don’t know, is the simplest I/O scheduler for Linux. NOOP scheduler inserts all incoming I/O requests into a simple FIFO queue and implements request merging. In other words, the scheduler assumes that the host is unaware of how to productively re-order requests. There for, noop handles all IO scheduling. Lets enable enable noop. […]

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Slow SSH Login | UseDNS=no

Problem: When SSH’ing into a server, connection, and login take a long time. Connect to a server Attempt to log in, and wait to see how long the connection takes. 10+ seconds is too long and should be investigated. Wait for the password prompt and then proceed to  cat /etc/ssh/sshd_config | less use vi to […]

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Sending logs to a syslog server

If you are running a linux server, go ahead and install rsyslog. yum install rsyslog You will need to edit the rsyslog config file. vi /etc/rsyslog.conf Add the following line. # ### begin forwarding rule ### # The statement between the begin … end define a SINGLE forwarding # rule. They belong together, do NOT […]

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Building a Syslog Server

Go ahead and deploy your server, if you havent yet take a moment to do so. Installing rsyslog: yum install rsyslog After the files have been installed, edit /etc/rsyslog.conf vi /etc/rsyslog.conf Once in, you’ll need to uncomment the following two lines $ModLoad imudp $UDPServer Run 514 $ModLoad imtcp $InputTCPServerRun 514 Save the file and close […]

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