Hi,  If you see the symdev show of the devices you would see that the "Device Config" shows as BCV, but when you see the "Back End Disk Director Information" in the same command,it would only show which RAID type it belongs to.  Hence symdisk would only show the RAID-type of the devices..(eg: RAID-1)  If you like to find the BCV devices which are part of the disk, please use the following command  # symdev list -bcv -sid XXX | grep DA:IT  eg: # symdev list -bcv -sid XXX | grep 0054 0054 Not Visible            ???:? 08C:D4  2-Way BCV Mir Asst'd       RW     501  # symdisk show 08C:D4 -sid XXX| grep 0054     2   300 FBA              0054 RAID-1         1   1  Ready               511  # symdev list -bcv -sid XXX | grep 08C:D4 0054 Not Visible            ???:? 08C:D4  2-Way BCV Mir Asst'd       RW     501 03C8 Not Visible            ***:* 08C:D4  2-Way BCV Mir N/Asst'd     RW     501
I tried the below command and its giving me only the raid-5 and the data disk . i cant see the BCV device but the EMC is saying , BCV is involved on the failed disk  command that i have used  symdisk -sid xxx show 11b:c7   Please let me know is there anyway we can find out the bcv's on that particular disk 
when disk is failed in DMX and that particuar disk is having BCV . How we can 
check the device id's through CLI