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eddiel
Contributor
Contributor

How to determine device driver: SCSILUN GENSCSI device

first ever post, i'm hoping somebody can tell me how to determine the device driver or the following luns mapped to a esx 3.5u4 installation. i realize these devices are not supported by vmware, but i'm curious how it is that the devices are being identified by the vmkernal and/or cos.

thanks, eddie

edl VCP
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AndreTheGiant
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You want to make a VM for backup? Using your library attached to your ESX?

You can do simply: power off your VM, add two generic SCSI device (with ID 1,x and 1,y to have on a different SCSI controller), then power on your VM anche check if you see the library and the tape.

Then install your backup software.

Andre

Andrew | http://about.me/amauro | http://vinfrastructure.it/ | @Andrea_Mauro
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eddiel
Contributor
Contributor

Andre, thanks for the response.

what i'm trying to determine is the specific driver the vmkernal utilizes with genscsi devices. ultimately, i would like to know is which vendor (vmware, hp, hba vendor?) would own support for these devices in the event issues would surface with there usage. is a generic driver being used? this particular device is actually a vtl, not a physical tape library.

thanks again,

edl

edl VCP
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mcowger
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The vmKernel simply doesn't assign a driver to these devices - they are passed through directly to the guest.






--Matt

VCP, vExpert, Unix Geek

--Matt VCDX #52 blog.cowger.us
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AndreTheGiant
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i would like to know is which vendor (vmware, hp, hba vendor?) would own support for these devices

As I know (but maybe something is changed) nobody support a solution of backup to tape in a VM.

is a generic driver being used?

You must use the same driver as a physical environment.

If you have backup vendor driver use them.

If you do not have backup vendor driver but have hardware vendor driver use them.

Otherwise use generic driver.

Andre

Andrew | http://about.me/amauro | http://vinfrastructure.it/ | @Andrea_Mauro
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eddiel
Contributor
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thanks for the response Matt.

i'm still trying to understand how the vmkernal/esx host processes these types of devices when first presented. more specifically, i'm very interested in understanding how the vmkernal i/o stack processes this type of device in a fc direct-attach scenario. the vmkernal is classifying these devices as scsi targets. further, the vmkernal is assigning deviceType and lunType variables along with a uuid. it would seem to me that at the the esx host, there is more than a simple pass-through occurring. at least initially, the kernal is interacting with this device in some manner. identifying that process is what i'm interested in. any vmkernal programmers onboard? Smiley Happy

and of course, the million dollar question: if there is no specific driver for vmware to support on these types of devices, it seems like that should open the door for inclusion on vmware's compatibility matrix, provided they actually work. support would then fall back on the generic device manufacturer.

any and all thoughts are welcome...

edl VCP
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mcowger
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So yes, the kernel does a little bit. It examines the SCSI VPD pages of each device, which contains its devicetype and a few other bit of info (OEM, usually, etc). Beyond that, its basically passthrough - no driver is loaded that binds to the device. The VPD/EVPD inspection is required to determine what kinds of the device the item is, which determines if vmware loads a driver for it or it (or interacts with it directly, as in the case of a device type of physical disk).

As far as HCL, obviously thats up to VMware/OEMs, but I wouldn't be surprised to find out that VMware doesn't accept certifications for device types outside of what they want to (arrays, NICs, etc).






--Matt

VCP, vExpert, Unix Geek

--Matt VCDX #52 blog.cowger.us