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Showing posts from December, 2014

PowerCli One-liners for VMware.

This post covers some powercli "One Liners" which will help the VMware admin's to make the day smooth and simplify their day-to-day tasks on VMware. Here we go...  Query the vmware tools on all virtual machines get-vm |% { get-view $_.id } | select Name, @{ Name=”Tools Status”; Expression={$_.guest.toolsstatus}}, @{ Name=”Tools Running Status”; E=$_.guest.toolsrunningstatus}} Query the nic type of all virtual machines Get-VM | Get-NetworkAdapter | Select-Object Parent,Type Query the disk type of all virtual machines get-vm | foreach-object -process {get-harddisk $_} | select-object storageformat | format-list Get VMs with Memory Reservations Get-VM | Get-VMResourceConfiguration | Where {$_.MemReservationMB -ne 0} | Select VM,MemReservationMBGet-VM | Get-VMResourceConfiguration | Where {$_.MemReservationMB -ne 0} | Select VM,MemReservationMB Get VMs with CPU Reservations: Get-VM | Get-VMResourceConfiguration | Where {$_.CpuReservationMhz -...

Lun Misalignment

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I am interested writing something about misalignment even though its old concept, but understanding misalignment will give a clear idea about basic storage architecture and iop's operations. Now a days most of the traditional infrastructure was migrated to virtualized platform which seems more flexible but misalignment triggered when we convert old platform with new, let me continue briefly :) What is Misalignment:   By default, many guest OSs, including most versions of Windows, attempt to align the first sector on a full track boundary. The installer/setup routine requests the cylinder/Head/Sector (CHS) information that describes the disk from the BIOS (PC firmware that manages disk I/O at a low level), or, in the case of many VMs, an emulated BIOS. The issue is that the CHS data hasn't actually corresponded to anything physical, even in physical machines, since the late 1980s. At larger LUN sizes, usually 8GB or more, the sectors per track (S number) is always repo...