Unlike VMware Server, Xen’s HyperVisor does not allow an easy collection of performance information. The management machine, called “Domain-0” is actually a privileged virtual machine, and thus – get its own small share of CPUs and RAM. Collecting performance information on it will lead to, well, collecting performance information for a single VM, and not…
I’ve had a belief for quite a while now that Linux, unlike other types of systems, was unable to produce any I/O SNMP information. I only recently found out that it was partially true – all production-level distros, such as RedHat (and Centos, for that matter) were unable to produce any output for any SNMP…
I love the tool Cacti. It’s a nice graphing tool, which helps a lot in system monitoring and management. Its logic, however, is not always obvious. The relationship between data types, host templates and graph templates is quite complex, and if you are to implement any non-default setup using Cacti, you better understand these relationships…
