Differences

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--- doc:appunti:linux:sa:raid [2022/01/31 11:44] – [Gestione RAID con mdadm] niccolo
+++ doc:appunti:linux:sa:raid [2024/04/17 12:44] (current) – [Gestione RAID con mdadm] niccolo
@@ Line 50: / Line 50: @@
 mdadm --manage /dev/md0 --fail /dev/sdb2
 mdadm --manage /dev/md0 --remove /dev/sdb2
+</code>
+=== Distruggere un volume RAID ===
+Per eliminare definitivamente un volume raid è necessario fermarlo, quindi è opportuno azzerare il sperblock di ogni componente, per evitare che l'auto-run dei volumi trovi la signature nelle partizioni e provveda a fare l'assemblaggio al successivo reboot:
+<code>
+mdadm --stop /dev/md4
+mdadm --zero-superblock /dev/sda7
+mdadm --zero-superblock /dev/sdb7
 </code>
@@ Line 182: / Line 192: @@
 which actually does not run the array if it is degraded (where the previous start was not).
+==== Rename an MD device permanently ====
+To geneate the configuration file **/etc/mdadm/mdadm.conf** you can use the tool **/usr/share/mdadm/mkconf**, which gathers information from the existing RAID volumes. The information are read from the **superblock** of the MD arrays and contains the **name** and **homehost**, so the file created contains lines like this:
+<file>
+ARRAY /dev/md/125  metadata=1.2 UUID=d92a8066:fc45b7d3:f916e674:3a695968 name=hostname:125
+</file>
+Editing ''mdadm.conf'' to rename a device (e.g. changing from **/dev/md/125** to **/dev/md/5**) will work on the next reboot (remember to update initramfs), but eventually ''mkconf'' will restore the name ''/dev/md/125'' on the next run. To change the name permanently you have to stop the RAID device and update the superblock:
+<code>
+mdadm --stop /dev/md/125
+mdadm --assemble /dev/md/5 --name=5 --homehost=newhostname --update=name /dev/sda5 /dev/sdb5
+</code>
 ===== Filesystem has unsupported feature(s) =====