Hi Narohna, You have made such a good question, let me answer you. 1 - In normal R1->R2 situation, and when you perform a timefinder snap or clone operation, from Host standpoint R1 is always RW for host and R2 is WD - Write Disable or what is the same Read Only to the host, since both vmax or dmx can't be RW at the same time to the host,  2 - Under normal conditions, I don't know if you deploy your timefinder operations thru SYMCLI or you have mainframe in your installation, anyway when you begin whith your copy or replica, it starts at local level(R1) and it propagates thru SRDF link to R2 Side, so your info is consistent at all times, but host has RW access only in R1 and RO to R2.  3 - In such special conditions, you can achieve to have both sides RW at the same time, for instance when you perform a "split" operation over the link or over a special pair of devices, in that particular case from Host Standpoint R1 and R2 will be seen as RW, but you will be able to copy only in one site, and it will accumulate owe tracks to the other side, and both sides will be sychronized when a establish operation takes place, Does it make sense to you?  Regards, and I hope it helps you  Pablo
In the -nocopy option, as per the product guide, it says that the copy happens when there is host I/O on target device or if there is a change in a track on the source device.  Can someone please clarify, in a TimeFinder/Clone operation, when and in what situations is the target device available for host I/O.  Thanks!
TimeFinder