The error “CHECK_NRPE: Error – Could not complete SSL handshake.” is usually caused by a mssing or wrong “allowed_hosts” configuration in /etc/nagios/nrpe. cfg. With an active debug option in the same config-file the active “allowed_hosts” setting is reported to the syslog (see log snippet above).
Step 1: “CHECK_NRPE: Error – SSL handshake failed” is sometimes (from what I’ve seen) an edge client issue. Step 2: Nagios clients typically store the nrpe-file.cfg file (provided by nagios-nrpe or nrpe-package) in /etc/nagios/nrpe.cfg (if installed from RPM).
In short, the NRPE handshake SSL error occurs when the NRPE server is having trouble communicating with the Nagios server. Today we saw how our support engineers solved this problem by adding the correct nrpe location file to the Nagios Into ip host. AVOID SERVER CRASH!
There are some mixed results, although most of them are simply due to the Nagios XI server’s IP address not being allowed to connect to NRPE. This can be specified in one of two places, depending on whether you are running xinetd when the daemon starts NRPE, and whether NRPE has its own fully committed daemon.
What is the importance of Nagios server in Nagios?
Allows Nagios to read its configuration from an entire directory, which helps you decide how to define individual electronic files. Uses topology to determine dependencies. Monitoring network services such as HTTP, SMTP, HTTP, SNMP, SSH, FTP, POP, etc. Helps to identify network nodes based on hierarchical parent nodes.
What is the difference between Nagios and Nagios XI?
Nagios Core requires up-to-date technical resources to install and configure your current organization’s monitoring infrastructure, as well as to perform day-to-day tasks. On the other hand, Nagios XI eliminates the need for potential customers to understand the command line with a user-friendly interface designed for non-technical users.
What are some of the advantages of Nagios XI over Nagios core?
The Complete Comparison Guide: Nagios XI vs Nagios Core
What is the difference between Nagios Core and Nagios XI?
Nagios Core requires advanced technical resources to manage the organization’s infrastructure setup, monitoring settings, and day-to-day tasks. Nagios XI allows users to quickly and efficiently upgrade monitoring settings, check statuses, and create and deploy enterprise-grade reports and dashboards.
Could not authenticate message could not be sent mailer error SMTP error could not authenticate?
“SMTP Error: Authentication Failed” is a serious error that often occurs when users send email via PHPMailer with SMTP authentication. This error occurs when the mail server is unable to establish an SMTP connection.

Ermias is a tech writer with a passion for helping people solve Windows problems. He loves to write and share his knowledge with others in the hope that they can benefit from it. He’s been writing about technology and software since he was in college, and has been an avid Microsoft fan ever since he first used Windows 95.