[Info-vax] Volume shadowing and current SCSI standards ?

[Stephen Hoffman]

On 2022-04-29 20:06:58 +0000, gah4 said:

> On Friday, April 29, 2022 at 8:23:03 AM UTC-7, Phillip Helbig (undress 
> to reply) wrote:
> 
> (snip)
> 
>> Will anyone use SCSI disks on x86?

The sorts of ancient and slow HDDs and parallel SCSI that you're 
familiar and accustomed to?  No. That written, much of the available 
x86-64 storage uses SCSI commands.

> As well as I know, all SATA disks will also accept SCSI commands, and 
> many systems run them that way.

SAS, ATAPI, iSCSI, iSER, SATA with SCSI translation, most USB storage, 
NVMe with SCSI translation, and other such storage, and other giblets 
are scuzzy, err, use SCSI commands.

ATA and SATA storage without the translation use ATA.

NVMe and NVMe-oF without the SCSI translation (and if you're not 
tunneling NVMe over SCSI, wheeeee!) goes direct.

If you're booted in a guest in a hypervisor, you're probably going to 
get an emulated LSI SAS controller or ilk and SCSI commands, and 
increasingly also an emulated NVMe controller sans SCSI commands.

> My choice would be NFS, though.

SMB won, in the general case. On OpenVMS, OpenVMS lacks SMB client 
support, and does have NFS client and server support, though both 
client and server need some help.

ps:
https://www.seagate.com/files/www-content/product-content/ssd-fam/nvme-ssd/nytro-xf1440-ssd/_shared/docs/an-introduction-to-nvme-tp690-1-1605us.pdf 

https://www.scsita.org/wp-content/uploads/2020/08/SAS_vs_NVMe_Interface_Smackdown-final2.pdf 

https://www.snia.org/sites/default/files/news/iSCSI-Future-Cloud-Storage-Doomed-NVMe-oF.pdf 


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