Monitoring Systems, SNMPv3 and the engineID

Sometimes encrypted SNMPv3 requests from Network Monitoring Systems (NMS) to devices just fail out of the blue. There is no reasonable explanation for the behaviour. In this article I will describe the problem, spectulate about the reason, and present a workaround (or solution, if you like). It works for me be I am not sure if I really found the real problem. At least it solves the problem which showes some real weired behaviour of the Zabbix server and the monitored device. But the problem not only occures in the Zabbix NMS but I also saw it in the CA's Spectrum system.

Continue reading

Zertifikate überwachen mit Zabbix

Es ist sehr ärgerlich, wenn das Zertifikat einer Webseite abgelaufen ist. Große rote Warnlampen springen den Besucher der Seite an, sie sind verunsichert und können im schlimmsten Fall sogar die Seite meiden. Der Administrator versucht verzweifelt das Zertifikat zu erneuern, was er das letzte Mal von ca. zwei Jahren gemacht hat und natürlich nun, wenn er es braucht, vergessen hat. Das gleiche gilt natürlich auch für Mailserver, die TLS Verschlüsselung für SMTP oder IMAP anbieten.

Continue reading

Monitoring Certificates with Zabbix

There's nothing more embarrasing than running a public website with expired certificates. Huge red warning message pop-up all over the place, users are concerned and might even avoid your site. The admin frantically trying to find out how to renew the certificate, something they either never done before or forgot how to do it. The same applies to mail servers that offer TLS encryption for SMTP or IMAP.

Continue reading