Hi, Recently, I try to do “adding/removing osds ” in ceph wiki Here is what I ave done <1> build a cluster with mon/mds/osd0 in the same machine “host0” And start it,everything is ok <2> follow the wiki ceph ,add a disk (/dev/sdb4)into host0 It’s ok ,”ceph osd dump ?o ? “show that there are two osds and state are in/up <3> write a 4G file pull out the osd1 when it about writes 2G ,the osd1 was marked down and 5 mins laster it was marked out,but use “df ?hl ” I find “/dev/sdb4 885G 2.7M 885G 1% /data/osd1” (it’s right?) so when re-insert the disk ,” fdisk ?l“ show me: Disk /dev/sda: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x000d6542 Device Boot Start End Blocks Id System /dev/sda1 * 1 3263 26210016 83 Linux /dev/sda2 3264 6134 23061307+ f W95 Ext'd (LBA) /dev/sda3 6135 121601 927488677+ 83 Linux /dev/sda5 3264 4307 8385898+ 82 Linux swap / Solaris /dev/sda6 4308 5612 10482381 83 Linux /dev/sda7 5613 6134 4192933+ 83 Linux Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x000549cb Device Boot Start End Blocks Id System /dev/sdc1 * 1 3263 26210016 83 Linux /dev/sdc2 3264 6134 23061307+ f W95 Ext'd (LBA) /dev/sdc4 6135 121601 927488677+ 83 Linux /dev/sdc5 3264 4307 8385898+ 82 Linux swap / Solaris /dev/sdc6 4308 5612 10482381 83 Linux /dev/sdc7 5613 6134 4192933+ 83 Linux And finally I can not start osd1 Because “/etc/init.d/ceph start osd1 ” do nothing Where is my problem?can you find it out for me? thanks -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html