As a addition, here are the relevant syslog lines there the hang is reported: Feb 26 11:34:03 ubuntu kernel: [ 1330.286619] INFO: task md127_reshape:10902 blocked for more than 120 seconds. Feb 26 11:34:03 ubuntu kernel: [ 1330.286624] Not tainted 4.15.0-29-generic #31-Ubuntu Feb 26 11:34:03 ubuntu kernel: [ 1330.286625] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Feb 26 11:34:03 ubuntu kernel: [ 1330.286626] md127_reshape D 0 10902 2 0x80000000 Feb 26 11:34:03 ubuntu kernel: [ 1330.286629] Call Trace: Feb 26 11:34:03 ubuntu kernel: [ 1330.286637] __schedule+0x291/0x8a0 Feb 26 11:34:03 ubuntu kernel: [ 1330.286640] ? md_wakeup_thread+0x31/0x60 Feb 26 11:34:03 ubuntu kernel: [ 1330.286645] ? raid5_release_stripe+0x11f/0x150 [raid456] Feb 26 11:34:03 ubuntu kernel: [ 1330.286647] schedule+0x2c/0x80 Feb 26 11:34:03 ubuntu kernel: [ 1330.286650] reshape_request+0x8df/0x9d0 [raid456] Feb 26 11:34:03 ubuntu kernel: [ 1330.286653] ? wait_woken+0x80/0x80 Feb 26 11:34:03 ubuntu kernel: [ 1330.286656] raid5_sync_request+0x339/0x3c0 [raid456] Feb 26 11:34:03 ubuntu kernel: [ 1330.286659] ? cpumask_next+0x1b/0x20 Feb 26 11:34:03 ubuntu kernel: [ 1330.286660] ? is_mddev_idle+0x92/0xf4 Feb 26 11:34:03 ubuntu kernel: [ 1330.286662] md_do_sync+0x8ca/0xf10 Feb 26 11:34:03 ubuntu kernel: [ 1330.286664] ? wait_woken+0x80/0x80 Feb 26 11:34:03 ubuntu kernel: [ 1330.286666] ? __schedule+0x299/0x8a0 Feb 26 11:34:03 ubuntu kernel: [ 1330.286668] md_thread+0x129/0x170 Feb 26 11:34:03 ubuntu kernel: [ 1330.286670] ? mddev_put+0x140/0x140 Feb 26 11:34:03 ubuntu kernel: [ 1330.286671] ? md_thread+0x129/0x170 Feb 26 11:34:03 ubuntu kernel: [ 1330.286672] ? wait_woken+0x80/0x80 Feb 26 11:34:03 ubuntu kernel: [ 1330.286675] kthread+0x121/0x140 Feb 26 11:34:03 ubuntu kernel: [ 1330.286676] ? find_pers+0x70/0x70 Feb 26 11:34:03 ubuntu kernel: [ 1330.286678] ? kthread_create_worker_on_cpu+0x70/0x70 Feb 26 11:34:03 ubuntu kernel: [ 1330.286681] ? do_syscall_64+0x115/0x130 Feb 26 11:34:03 ubuntu kernel: [ 1330.286683] ret_from_fork+0x35/0x40 kernel version: 4.15.0-29-generic Greetings Brian
