showvv vs showvlun output

[AR_Hillbilly]

I assume I am missing some basic understand of the difference between a virtual volume and a virtual LUN.  I thought a vv became a vlun once exported to a host or something like that.  When running showvv I get 1294 total volumes and when running showvlun I get 1190 total luns. 

From looking at the help page for "showvv" it states I can list exported VV's for a certain host and the example is;

The following example displays space usage information for thin provisioned
VVs that are exported to host hname:

cli% showvv -s -p -prov tp* -host hname

Again I am assuming "hname" above should be substitued with a valid hostname since running the above command returns "hname not found"

Now i don't have any thin provisioned volumes so I am using "cpvv" as listed for prov when listing all the VV's with showvv.

I get a return when running "showvv -s -p -prov cpvv" but get "no vv listed" when adding in the -host option such as;

showvv -s -p -prov cpvv -host foobar

However, when I run "showvlun -host EEFCURAMDBUAT" I get a listing of volumes that are exported to that host.

So I am just lost as to why the -host option for showvv does not provide me any VV's for that host as suggested by the help page.

Thanks for your time,

Justin

[Sheldon Smith]

Hello,

FIrst of all, the HPE 3PAR Command Line Interface reference guide is your friend. For that matter, since you're in the command line, help is also your friend. For example "help showvv" or even "cmore help showvv". Likewise "help showvlun". And "cmore" breaks things into pages.

A virtual volume is a container. Like a USB flash drive in your pocket. When you create a VLUN, you are in essense plugging the flash drive in. You now have a virtual LUN. You still have a virtual volume.

showvv shows all the virtual volumes, base and snapshot alike.

showvlun shows all the virtual lun paths. Of which there are presumably at least two and possibly several for each exported virtual volume. And it shows all the virtual lun templates: LUN number, VVname and hostname.

You may rather use "showvlun -t" which shows just the templates and not the huge list of LUN paths. 

[Sheldon Smith]

And it's been a while since I looked at the 3PAR commands. Looking at the vvlun help in the CLI manual, if you are using host sets, you will need to specify the host set with the "set:" tag prefaced. See the examples in the documentation.

[AR_Hillbilly]

Sheldon,

Thank you for you quick response.  You have a USB flash drive, you plug it in, not sure what action to corollate to the plugging in unless it's the export to the host.  In my case there doesn't appear to be two or more vlun paths for each virtual volume unless showvlun is not showing all of them.  Since I have more VV's then VLUN's, 1294 VV's and 1190 VLUN's.

The help page only goes so far, as I stated it states me being able to list the VV's that are exported to a host.  Yet to figure out from the help page how to make that work ,as the examaple given doesn't work.

Maybe the command reference will correct that mistake or be clearer what I am missing as I am not getting a syntax error.

The "showvlun -t" just confuses the issue for me.  As I have the same number with or without the "-t"

So when I go to the SSMC and delete a Virtual Volume, what am I deleting?  The VLUN + the VV?

Ultimately I am trying to get a listing of assigned LUNs to a given host and then I want to remove those LUN's.  Meaning completely delete the VV/VLUN from the system.  I am doing it from the command line because I have hundreds to delete and it will take way to long via the SSMC.

So not sure if I need to use the removevv or removevlun command to accomplish that.

Thanks,

Justin

[Sheldon Smith]

Yes; plugging a USB drive is correlates to creating a VLUN.

It reads like your systems have single paths between the host and the 3PAR?

When you  delete a virtual volume in SSMC, you are deleting the volume. As I recall, it will tell you if the volume is exported and if you would like to remote the VLUN first. The VLUN has to be removed before the volume is removed.

And in your case, you would use the removevlun command.

Might I suggest you reach out to HPE Pointnext Technology Services for assistance....

[AR_Hillbilly · Accepted solution]

Sheldon,

I don't have any hosts with a single path to the 3par system so that can't be the case.

I was able to make it work, just moved the export with removevlun and then removed the VV with removevv.  Ran into some issues as some of the volumes where in volume sets but figured out that process as well.

Thanks for your time and support.