What steps will reproduce the problem? 1. plug in USB external drive /dev/disk2 #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *500.1 GB disk2 1: EFI 209.7 MB disk2s1 2: ZFS puddle 499.8 GB disk2s2

2. rsync to the ZFS filesystem

What is the expected output? What do you see instead? Expect it to complete the 100gb rsync operation. Instead crashes the computer after transferring a few tens of gb.

What version of the product are you using? On what operating system? 74.1.0 Mac OS X 10.7.2

Please provide any additional information below. The drive is left in a state where it does not appear when the machine is rebooted after the crash. I have to cycle the power on it. The drive has not been used before but it may be having an actual I/O failure as indicated in the panic report. I thought it might be useful to see the location of the crash which is fs/zfs/zio.c:918.

I have attached the report. I will try a different USB external drive and I could try to set up a pool on a partition of the internal drive but am hesitant to do it if the software is likely to continue to cause problems. Is it working well in general?

It seems that this was caused by a hardware failure in the drive. The crash can be duplicated by unplugging a USB drive without exporting it. If I use the finder to eject the drive but do not also export it, it still shows up in the zpool list and eventually the machine crashes in the same place.