Hello, I have a couple of questions about device-mapper. I've had a look at the source and could not see an obvious answer. Firstly, is it possible to utilize one device-mapper module from another without redirecting to the actual device? For example, if I create a new device-mapper module that maps blocks over the network and I want to layer dm-crypt on top, am I forced to first map my device, then map dm-crypt to this device. It would be extremely convenient to be able to "layer" them without this requirement, so I could effectively call dm-crypt to do mapping directly from my module. My second question is somewhat related. I am thinking about doing a network based block device running on device mapper. What is the "best" way of communicating with user-space from a device-mapper module? I would like to do most of the network stuff in user-space to take advantage of existing cluster communication infrastructure, so it would need to be fairly high-speed for transfer of blocks to/from user-space. So, to summarize in a less rambling way :)... Can device-mapper modules "chain" together without bouncing back through device nodes? What is the "best" way of communicating at high volume with user-space from a device-mapper module? Regards, Alec -- Evolution: Taking care of those too stupid to take care of themselves.