Mike Snitzer wrote:
Here are the steps to reproduce reliably on SLES10 SP1: 1) establish a raid1 mirror (md0) using one local member (sdc1) and one remote member (nbd0) 2) power off the remote machine, whereby severing nbd0's connection 3) perform IO to the filesystem that is on the md0 device to enduce the MD layer to mark the nbd device as "faulty" 4) cat /proc/mdstat hangs, sysrq trace was collected
That's working as designed. NBD works over TCP. You're going to have to wait for TCP to time out before an error occurs. Until then I/O will hang.
-- Paul