I’ve decided to convert my blog to english.
At least it was Fabian Lenz (@lenzker; vxpertise.net) who gave me the last tick to do this.
The next time I will translate my older posts, but this will take some time :)
Author: Alexander (Page 31 of 34)
In my last training Fabian Lenz and I discuss pro and con of power management in ESXi.
We thought DPM is mostly used in VDI-environments. In those environments the savings would be the best, because the virtual desktops didn’t work at night and many of the ESXi hosts could be powered off. But DPM ist not the only thing which affects the power consumption. ESXi could use ACPI C- and P-States from the CPU to control the power of the physical cores. Fabian experiements with a bigger VDI environment and gets interessting informations with activated DPM (watch his blog).
In vSphere 5.5 and 6.0 a new command was given to esxcli. With this command you can reclaim deleted blocks on thin-provisoned LUNs.
You could run the mechanism in production time. This might sound good…. Our maintainance windows gets smaller and smaller with every new service and if you could do maintainance when everybody could work is that great.
BUT one moment!
The ESXi host which runs the reclaim would get very high cpu usage and might costops VMs within the host. Especially the first run will take a lot of time.
The storage multipathing policy in ESXi configures in which way ESXi uses the availiable paths his LUNs.
This article discribes the different policies und explaines how to change policies for connected LUNs. Additional I show how to change the default policies for new connected LUNs.
