Use Paravirtualized Devices On Your Virtual Machines

This is post #13 in my December 2013 series about Linux Virtual Machine Performance Tuning. For more, please see the tag “Linux VM Performance Tuning.” para- a prefix appearing in loanwords from Greek, most often attached to verbs and verbal derivatives, with the meanings “at or to one side of, beside, side by side” ( parabola; paragraph; parallel; paralysis ),”beyond, past, by” ( paradox; paragogue ); by extension from these senses, this prefix came todesignate objects or activities auxiliary to r derivative of that denoted by the base word ( parody;paronomasia ), and hence abnormal or defective ( paranoia ), a sense now common in modernscientific coinages ( parageusia; paralexia ). Paravirtual drivers are ones where the virtualization platform does …

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How to Change SCSI Controllers on your Linux VM

A question from Matt Vogt prompted this, where he wants to go from the BusLogic  SCSI controller to the LSI Logic SAS controller. It’s actually a straightforward conversion if you have the right steps. This is based on Red Hat Enterprise Linux 3, 4, and 5, but the principle should be the same for everything. It’s basically: snapshot, change config files, change hardware. Red Hat Enterprise Linux 6, in contrast, appears to have all the LSI Logic, parallel & SAS, drivers, as well as the paravirtual SCSI drivers, so all you need to do is shut the VM down and change the type of SCSI controller you’re using. I always recommend trying this on a test VM before you try …

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