Neil, >Yes. >Somehow both sdb and sdb3 have a superblock for the same array. Must have >been a typo somewhere I suspect. >You should remove the one you don't want: > mdadm --zero-superblock /dev/sdb >then it should all work nicely again. Unfortunately, the above command gave the following error : root@server2:~# mdadm --zero-superblock /dev/sdb mdadm: Couldn't open /dev/sdb for write - not zeroing Do you know how to work around? Tony "Warning: The information contained in this email and any attached files is confidential to BAE Systems Australia. If you are not the intended recipient, any use, disclosure or copying of this email or any attachments is expressly prohibited. If you have received this email in error, please notify us immediately. VIRUS: Every care has been taken to ensure this email and its attachments are virus free, however, any loss or damage incurred in using this email is not the sender's responsibility. It is your responsibility to ensure virus checks are completed before installing any data sent in this email to your computer." -- 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