On 11/28/2016 12:26 PM, Randall C. Grimshaw wrote: > I have made the mistake of booting a centos-6.8 live cd to manipulate a centos 5 system. > as a result md5 has become md122, md2 has become md125, md4 has become md126, md0 has become md127, and most unfortunately md3 has also become md122. This is normal and expected for a livecd -- the numbering comes from the mdadm.conf file in the initramfs, unless that mdadm.conf file excludes arrays for later assembly (when the rootfs is available). Many livecd initramfs scripts try to assemble everything, so the numbers are allocated from 127 down. Usually you can find a boot parameter to suppress assembly. > smartctl shows that the WD brand drives do support SCT > mdadm --examine was used to reveal the mish-mash using uuid numbers compared with the file /etc/mdadm.conf also referencing /etc/fstab. Eww. You should not be counting on /dev/mdX numbering in your fstab. Specifically for this reason. Use LABEL= or UUID= syntax in fstab. > can someone kindly tell me the mdadm command to put the correct numbers back. No need. When you boot back into your normal system, its initramfs will supply this information. If you are changing the info, make sure you rebuild your initramfs, so the updated mdadm.conf file is included. Phil -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html