Vivek, 1) Basically we map the LUN from storage arrary to one of linux host . Linux host sees that LUN with mutlipath ( dm-multipath) abstact device /dev/mapper/LUNID . Linux host can mount that lun and do some read and write operation on that . We want to cature those writes and send those writes to another appliance . we will use that appilance for CDP( continues data protection) of that LUN . 2) My idea is To track writes on the mapped lun in Linux, Can we instantiate a write tracking Device Mapper device stacked on top of the mapped lun device ( /dev/mapper/LUIN) ?. Then, whenever the write tracking Device Mapper device receives write request, it tracks the write. After that, it passes the write request down to the underlying lun device. In addition, to track writes to a Lun device, Linux host needs to be told to access the write tracking device instead of the LUN device itself. Kind of Host side write splitter in Storage domain, Do we have any implemention which does this ?. or the work is in progress which we can leverage ?. ?. Please kindly share any web links or pointers on this . Thanks in advance . /Suresh -----Original Message----- From: Vivek Goyal [mailto:vgoyal@xxxxxxxxxx] Sent: Friday, January 09, 2015 7:53 PM To: device-mapper development Subject: Re: Device mapper target driver for Write tracking or Write split On Thu, Jan 08, 2015 at 09:23:21PM -0800, Suresh Babu Kandukuru wrote: > Hi List, > > > > I am mainly looking at write tracking Device Mapper device . Do we have any device mapper target driver for write tacking or write splitting ?. or any work happening on this to leverage ?. Please kindly share any web links or pointers on this . Thanks in advance . > Hi Suresh, Could you give more details. What is write tracking/splitting and what are you planning to do with that. Thanks Vivek -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
