OnlySandy wrote: In thinprovisioning , I belive the first device which we add to Pool ,the Pool will show dev config same as the config of device added to it. If i add Raid6(6+2) device to newly created pool , the pool will show Dev Config in symcfg list -pool as Raid6 (6+2) only. Also i belive i wont be able to add amy 2-Way-Mirror device to pool having  Dev config of Raid6(6+2)

you are correct, you can't mix different protection types in one pool:

DATA devices are similar to SAVE devices, in that they are not visible to the host and
must be contained in a pool before they can be used. Thin pools can only contain
devices of the same emulation and protection type, however, the DATA devices can
be different sizes

Also is there any command quivalent to symmask list assign -sid XXXX -devs in vmax. I checked in PDF it showing "symaccess list assignment -dev XXXX" but its not working at my place.

you are trying to list devices that are masked to specific WWN ? If you know initiator group name you can list what's masked to it:

symaccess -sid 1234 list devinfo -ig ig_groupname

Thanks Dynamox for clarification. I am trying to list the WWN to which the dev is masked.

I use to give "symmaskdb -sid XXXX list assign -dev XXXX,XXXX" and it gives me list of HBA's and FA's to which devices are masked.

Again i checked in 7.0 pdf same commands is there only symmaskdb replaced by symaccess but its not working.

I done "symmaccess -help " but cant find the "assign" option , so it obious that my command will not work.

So just wondering if anything such there or not !!!!!!!

One more thing , i saw most of the people they use Raid6 (6+2) when working with pool concept or thin provisionig.

Why Raid6 only ?? Due to dedicated parity ?? Any ways any disk failure in raid will impact a huge number of thin devices a they are spread in backend.

Thn why raid 6 not mirror . (Not raid 5 may be because  of distributed parity, correct me if i am wrong.)

Thanks dynamox. I need to check the symcli version. the command not working . Not even showing the option  for "list assignment"

i don't see that option in 7.0 but i do see it in 7.1.1

Thin pools can only contain devices of the same emulation and protection type.

What is emulation here? I am not familiar with the term emulation , what does it mean?

Device emulation

All host I/O transactions with an array of Symmetrix disk devices are managed by
the Enginuity operating environment, which runs in the Symmetrix I/O subsystem
(channel directors and disk directors). Because each of the physical disks are
indirectly seen as part of the I/O protocol, Symmetrix devices are presented to the
host with the following configuration or emulation attributes:
◆ Each device has N cylinders. The number is configurable (blocks ÷ 960).
◆ Each cylinder has 15 tracks (heads).
◆ Each device track in a fixed block architecture (FBA) has 64 blocks of 512 bytes.
(For non-FBA operating systems, the blocks are recognized without regard to the
number of bytes.)
Note: With Enginuity 5771, track sizes for FBA devices have been increased to 64K.

Emulation types: fba, ckd,ckd3390,ckd3380,as400, celerra

Most commonly used emulation type is FBA, this is what your open systems use ( Unix/Linux, vSphere, Windows)