Hi Lon, I found a very interesting bug that manages to hang the entire cluster. Setup is a 3 nodes cluster, with no fancy stuff running at all (i will be able to show it to you next wed as it lives on my laptop ;)). <quorumd label="test1"> <heuristic program="ping 192.168.1.1 -c1 -t1" score="1" interval="2" tko="3"/> </quorumd> test1 is a 1GB shared AOE device between the 3 nodes. the cluster starts without problems. After firing up qdiskd -f -d: qdiskd -f -d  debug: Loading configuration information  debug: Heuristic: 'ping 192.168.1.1 -c1 -t1' score=1 interv =2 tko=3  debug: 1 heuristics loaded  debug: Quorum Daemon: 1 heuristics, 1 interval, 10 tko, 0 votes open_partition: seek: Invalid argument qdisk_validate: open of /dev/sda2 for RDWR failed: Illegal seek qdisk_verify: Illegal seek  info: Quorum Partition: /dev/etherd/e1.0 Label: test1  info: Quorum Daemon Initializing  info: Heuristic: 'ping 192.168.1.1 -c1 -t1' UP  debug: Node 2 is UP  debug: Node 3 is UP  info: Initial score 1/1  info: Initialization complete  notice: Score sufficient for master operation (1/1; required=1); upgra ng  debug: Making bid for master  info: Assuming master role A few seconds after the node assume master role, it hangs. The others will follow in a matter of seconds. aisexec is stalled in recv(.. No way to recover. kill -9 all over is required. In attachment is a qdiskd strace from all the 3 nodes started at the exact same time. Fabio PS I wonder if we are hitting this: from qdisk/disk.c: /* * All IOs must be of size which is a multiple of 512. Here we * just add in enough extra to accommodate. * XXX - if the on-disk offsets don't provide enough room we're cooked! */ -- I'm going to make him an offer he can't refuse.