So I have a kludgy way of pinning writes to one vdev (see my other post - http://www.opensolaris.org/jive/thread.jspa?threadID=85261&tstart=0). This doesn't quite get the read-only vdev I wanted (writes are still occurring in the vdev label). My ultimate goal is to have an interchangeable vdev which will serve as the base of all my filesystems.
In my investigation to complete an interchangeable vdev - I've noticed 48 mystery bytes being written at the end of the nv-pair section of the vdev label. From 0x0001 FFD0 to 0x0002 0000 on a vdev, there are 48 bytes of data that gets changed on import. The on-disk specification states that 16K - 128K is dedicated to name value pairs (0x0000 4000 to 0x0002 0000). I'm going to start tracing through the import source now w/ a debugger, but I'm not sure how easy it is going to be to see when this section is written (for my own sake, I hope it's grossly obvious but things usually don't work out that way...). If you know what these 48 bytes might be - please let me know! I'll post what I find. ~Mike -- This message posted from opensolaris.org
