From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ramon Hofer Subject: Enlarging device of linear array again (Thank you Stan!) Date: Tue, 20 Sep 2016 21:34:42 +0200 Message-ID: <20160920213442.1559310f@hoferr-X240.hofer.rummelring> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hi all In 2012 this list - especially Stan Hoeppner - helped me setting up a linear RAID containing four RAID5. Thank you so much again! It is still working amazingly well :-D Now I am at the point where I want to add more storage but have no more slots. As discussed in 2013 I will replace four discs with partitions from a larger HDD and add the remaining space to a new RAID5. md2 should be replaced: $ sudo mdadm -D /dev/md2 /dev/md2:         Version : 1.2   Creation Time : Sun Jun 17 20:08:48 2012      Raid Level : raid5      Array Size : 4395412224 (4191.79 GiB 4500.90 GB)   Used Dev Size : 1465137408 (1397.26 GiB 1500.30 GB)    Raid Devices : 4   Total Devices : 4     Persistence : Superblock is persistent     Update Time : Tue Sep 20 09:12:16 2016           State : clean  Active Devices : 4 Working Devices : 4  Failed Devices : 0   Spare Devices : 0          Layout : left-symmetric      Chunk Size : 128K            Name : media-server:2  (local to host media-server)            UUID : 1c74447b:33070712:cfcfa5af:cbfea660          Events : 2449     Number   Major   Minor   RaidDevice State        0       8       64        0      active sync   /dev/sde        1       8       80        1      active sync   /dev/sdf        2       8       96        2      active sync   /dev/sdg        4       8      112        3      active sync   /dev/sdh $ sudo fdisk -l /dev/sd[efgh] Disk /dev/sde: 1.4 TiB, 1500301910016 bytes, 2930277168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x00097014 Disk /dev/sdf: 1.4 TiB, 1500301910016 bytes, 2930277168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x0007694c Disk /dev/sdg: 1.4 TiB, 1500301910016 bytes, 2930277168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x000da169 Disk /dev/sdh: 1.4 TiB, 1500301910016 bytes, 2930277168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x000beebc $ sudo mdadm --examine /dev/sd[efgh] /dev/sde:           Magic : a92b4efc         Version : 1.2     Feature Map : 0x0      Array UUID : 1c74447b:33070712:cfcfa5af:cbfea660            Name : media-server:2  (local to host media-server)   Creation Time : Sun Jun 17 20:08:48 2012      Raid Level : raid5    Raid Devices : 4  Avail Dev Size : 2930275120 (1397.26 GiB 1500.30 GB)      Array Size : 4395412224 (4191.79 GiB 4500.90 GB)   Used Dev Size : 2930274816 (1397.26 GiB 1500.30 GB)     Data Offset : 2048 sectors    Super Offset : 8 sectors    Unused Space : before=1968 sectors, after=304 sectors           State : clean     Device UUID : 270f29c9:0a36cd7a:27324b70:7f4e929b     Update Time : Tue Sep 20 09:12:16 2016        Checksum : dc24915c - correct          Events : 2449          Layout : left-symmetric      Chunk Size : 128K    Device Role : Active device 0    Array State : AAAA ('A' == active, '.' == missing, 'R' == replacing) /dev/sdf:           Magic : a92b4efc         Version : 1.2     Feature Map : 0x0      Array UUID : 1c74447b:33070712:cfcfa5af:cbfea660            Name : media-server:2  (local to host media-server)   Creation Time : Sun Jun 17 20:08:48 2012      Raid Level : raid5    Raid Devices : 4  Avail Dev Size : 2930275120 (1397.26 GiB 1500.30 GB)      Array Size : 4395412224 (4191.79 GiB 4500.90 GB)   Used Dev Size : 2930274816 (1397.26 GiB 1500.30 GB)     Data Offset : 2048 sectors    Super Offset : 8 sectors    Unused Space : before=1968 sectors, after=304 sectors           State : clean     Device UUID : fe2fffdc:6d072a9d:87757913:ae7365db     Update Time : Tue Sep 20 09:12:16 2016        Checksum : f558ec26 - correct          Events : 2449          Layout : left-symmetric      Chunk Size : 128K    Device Role : Active device 1    Array State : AAAA ('A' == active, '.' == missing, 'R' == replacing) /dev/sdg:           Magic : a92b4efc         Version : 1.2     Feature Map : 0x0      Array UUID : 1c74447b:33070712:cfcfa5af:cbfea660            Name : media-server:2  (local to host media-server)   Creation Time : Sun Jun 17 20:08:48 2012      Raid Level : raid5    Raid Devices : 4  Avail Dev Size : 2930275120 (1397.26 GiB 1500.30 GB)      Array Size : 4395412224 (4191.79 GiB 4500.90 GB)   Used Dev Size : 2930274816 (1397.26 GiB 1500.30 GB)     Data Offset : 2048 sectors    Super Offset : 8 sectors    Unused Space : before=1968 sectors, after=304 sectors           State : clean     Device UUID : f27f55c2:f66f5fe9:02943932:2cf47cca     Update Time : Tue Sep 20 09:12:16 2016        Checksum : 34bc439e - correct          Events : 2449          Layout : left-symmetric      Chunk Size : 128K    Device Role : Active device 2    Array State : AAAA ('A' == active, '.' == missing, 'R' == replacing) /dev/sdh:           Magic : a92b4efc         Version : 1.2     Feature Map : 0x0      Array UUID : 1c74447b:33070712:cfcfa5af:cbfea660            Name : media-server:2  (local to host media-server)   Creation Time : Sun Jun 17 20:08:48 2012      Raid Level : raid5    Raid Devices : 4  Avail Dev Size : 2930275120 (1397.26 GiB 1500.30 GB)      Array Size : 4395412224 (4191.79 GiB 4500.90 GB)   Used Dev Size : 2930274816 (1397.26 GiB 1500.30 GB)     Data Offset : 2048 sectors    Super Offset : 8 sectors    Unused Space : before=1968 sectors, after=304 sectors           State : clean     Device UUID : 642511df:7f5d1022:a1b40e7b:6ebd37c6     Update Time : Tue Sep 20 09:12:16 2016        Checksum : ceb8c19b - correct          Events : 2449          Layout : left-symmetric      Chunk Size : 128K    Device Role : Active device 3    Array State : AAAA ('A' == active, '.' == missing, 'R' == replacing) I hope to simply do the following steps: ## Replace old disk with new partitions # Step 1: Create partitions on disk $ sudo fdisk /dev/sde create 1465137408 (1397.26 GiB 1500.30 GB) partition and a second on with the rest # Step 2: Replace old disk with new partition $ sudo mdadm --manage /dev/md4 --add /dev/sde1 # Step 3: Wait until rebuilt # Step 4: Repeat steps 1-3 for /dev/sd[fgh] ## Add new partitions # Step 5: Create new Raid5 sudo mdadm -C /dev/md5 -c 128 -n4 -l5 /dev/sd[efgh]2 # Step 6: Add new Raid5 to linear sudo mdadm --grow /dev/md0 --add /dev/md5 # Step 7: Grow filesystem sudo xfs_growfs /mnt/media-raid I am using 4 TB WD red to replace the 1.5 TB disks. Do you think this could work? Are there any pitfalls? Should I unmount the array to perform all these steps? It might be safer since there is no redundancy during the replacement? I just wanted to check first before making any mistakes. Instead of maybe afterwards asking for help recovering my data :-P Best regards, Ramon