Create clone

Straight from Solution Enabler manuals:

Understanding copy session limits
The Symmetrix array is currently limited to 16 sessions per source, which can be used for TimeFinder/Mirror, TimeFinder/Clone, TimeFinder/Snap, SRDF/Star, ORS, or SDDF operations. This limits the number of available clone copies that can be created.
For example, if you have a standard device with two paired BCV devices, you can
only create up to 14 copy sessions for that standard device. In addition, if you are
running in emulation mode, this number is decremented an additional two sessions
per single BCV relationship.
Copy sessions created using the -copy option to create full data copies are limited to eight concurrent sessions, with up to an additional eight CopyOnAccess sessions, for a total of 16 sessions.
Copy sessions created using the -differential option use two session slots.



Put all 16 metadevices in a DG with their corresponding 16 target metavolumes and use symclone command as suggested in manuals

symdg create foo
symld -g foo -sid xxx add dev 0BAD
symld -g foo -sid xxx add dev CAFE
... (repeat for other 14 source devices)
symld -g foo -tgt add dev BEEF
symld -g foo -tgt add dev B00B
... (repeat for other 14 target devices)
symclone -dg foo create DEV001 DEV002

(just to give you a quick hint)



It depends on the OS.. Windows dislikes different drives with same signature. HPUX will hate different PV with same PVID/VGID. AIX and VxVM will complain...
Some OS offer tools to handle this (notably, hpux and its vgchgid command). And you can also dig our SIU (Symmetrix Intergration Utilities) that offer usefull tools for Windows.

Thanks - we can put the devices in a file and do the symclone?

symclone -sid xxx -file -copy -differential create

The requirement here is we need concurrent clones.

I mean one source and two clone with activate at same time. So if I need to create with file option , how is it possible? in the file shall I mention one source and two target devices?

Also , if I add 16 devices to group, I have to use symclone command for all devices
or to thr group?

symclone -dg foo create DEV001 DEV002

is the above command need to be repeated for all 16 devices?

This is from your reply

symdg create foo
symld -g foo -sid xxx add dev 0BAD
symld -g foo -sid xxx add dev CAFE
... (repeat for other 14 source devices)
symld -g foo -tgt add dev BEEF
symld -g foo -tgt add dev B00B
... (repeat for other 14 target devices)
symclone -dg foo create DEV001 DEV002

you can have two files, one contains in column 1 your source devices in second column your set 1 clones, in second file first column would be your source devices and in second column your set 2 clones. When you work with file you will not need to call out every single device like you do with devices group if you place both clone sets in the same group. You could create two device groups and place source devices in two different groups but in order to do that you would need to change an option in the options file to allow for that.

If I create two device files ( one contain source --and clone1 and other contain source and ---clone 2) , what will be the symclone command for create and activate so that I have same data on both the clones?

i am not sure you can do that with files, you believe you have to use device groups with "-concurrent" option.

I don't know if you can activate two different clones at the same time ..
I'm not 100% sure but AFAIK you can activate only a single clone. If you need two clones, issue two commands. But the two clones will be two different PIT (images at different time).

To have 2 clones with exact same PIT: make one clone, then clone the clone.

-bh

I am not expert in DMX - but clone of a clone is not possible in Clarrion.
how about DMX? have you tried this?

Yes, it is possible with Symmetrix, but you may have to terminate the first clone session before setting up the "clone of a clone" session. This would mean that each clone session would be a full session, not an incremental or differential session, but each clone would have the same point in time copy of the source data.

Maybe someone with more experience with clones can speak if the first clone's session would need to be terminated before setting up the clone of a clone. Maybe the newer DMX code allows this? Not sure.

Hope this helps more than confuses.

-bh

I agree with you. This is a nice workaround .. You can take the first clone, wait for full copy to complete and next terminate the clone session. You can later use the "original" clone as a stamp and clone it again.

Once upon a time we had only R1 and R2 . .now we have R12, R21 and a lot of other interesting new features .. I can't talk about the future (I really have no idea about what we'll see with new codes) however right here right now we can't clone a clone. Unless you terminate the first one before

Message was edited by:
Stefano Del Corno

Added last statement to clean up my sentence

It is possible in Clariion as well, just like in DMX: just end the pair relationship first and then create a clone of the clone

Dynamox unfortunatly I'm still not 100% sure .. I used -concurrent only a few times and only with snaps.. Manuals state that -concurrent allows you to establish an additional available target when used with "symclone establish" but doesn't explain if you can establish more then one target in a single command. And moreover doesn't explain if you can split/activate more then one target at the same time.

Time permitting I'll try to run some tests and share the output

awesome ..if you can't let me know ..i'll try it on my box.