Changes between Version 2 and Version 3 of TipAndDoc/storage/RAID/rescue/RAID1

Timestamp:

Mar 24, 2011 11:14:57 PM (13 years ago)

Author:

mitty

Comment:

--

TipAndDoc/storage/RAID/rescue/RAID1

@@ -258 +258 @@
   vgnfs   1   0   0 wz--n- 1.94G 1.94G
 }}}
+
+ == degraded RAID1 ==
+ === devices ===
+ * root@Knoppix:~# ls -l /dev/sd?
+{{{
+brw-rw---- 1 root disk 8,   0 Mar 25  2011 /dev/sda
+}}}
+
+ === modprobe ===
+ * root@Knoppix:~# cat /proc/mdstat
+{{{
+cat: /proc/mdstat: No such file or directory
+}}}
+
+ * root@Knoppix:~# modprobe md_mod
+
+ * root@Knoppix:~# cat /proc/mdstat
+{{{
+Personalities :
+unused devices: <none>
+}}}
+
+ * root@Knoppix:~# mdadm -E /dev/sda1
+{{{
+/dev/sda1:
+          Magic : a92b4efc
+        Version : 00.90.00
+           UUID : 32578407:6f33f50b:893cf340:745f5dce
+  Creation Time : Thu Mar 24 17:31:36 2011
+     Raid Level : raid1
+  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
+     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
+   Raid Devices : 2
+  Total Devices : 2
+Preferred Minor : 0
+
+    Update Time : Thu Mar 24 21:25:32 2011
+          State : clean
+ Active Devices : 2
+Working Devices : 2
+ Failed Devices : 0
+  Spare Devices : 0
+       Checksum : e3889399 - correct
+         Events : 0.34
+
+
+      Number   Major   Minor   RaidDevice State
+this     0       8       17        0      active sync   /dev/sdb1
+
+   0     0       8       17        0      active sync   /dev/sdb1
+   1     1       8       33        1      active sync   /dev/sdc1
+}}}
+
+ * root@Knoppix:~# mdadm -Es
+{{{
+ARRAY /dev/md0 level=raid1 num-devices=2 UUID=32578407:6f33f50b:893cf340:745f5dce
+}}}
+
+ === method 1 ===
+ * root@Knoppix:~# mdadm -A /dev/md0 -u 32578407:6f33f50b:893cf340:745f5dce
+{{{
+mdadm: /dev/md0 has been started with 1 drive (out of 2).
+}}}
+
+ === method 2 ===
+ * root@Knoppix:~# mdadm -A /dev/md0 /dev/sda1
+{{{
+mdadm: /dev/md0 has been started with 1 drive (out of 2).
+}}}
+
+ === result ===
+ * root@Knoppix:~# cat /proc/mdstat
+{{{
+Personalities : [raid1]
+md0 : active raid1 sda1[0]
+      2047936 blocks [2/1] [U_]
+
+unused devices: <none>
+}}}
+ * root@Knoppix:~# mdadm -Ds
+{{{
+ARRAY /dev/md0 level=raid1 num-devices=2 UUID=32578407:6f33f50b:893cf340:745f5dce
+}}}
+ * root@Knoppix:~# mdadm -D /dev/md0
+{{{
+/dev/md0:
+        Version : 00.90.03
+  Creation Time : Thu Mar 24 17:31:36 2011
+     Raid Level : raid1
+     Array Size : 2047936 (2000.27 MiB 2097.09 MB)
+  Used Dev Size : 2047936 (2000.27 MiB 2097.09 MB)
+   Raid Devices : 2
+  Total Devices : 1
+Preferred Minor : 0
+    Persistence : Superblock is persistent
+
+    Update Time : Thu Mar 24 21:25:32 2011
+          State : clean, degraded
+ Active Devices : 1
+Working Devices : 1
+ Failed Devices : 0
+  Spare Devices : 0
+
+           UUID : 32578407:6f33f50b:893cf340:745f5dce
+         Events : 0.34
+
+    Number   Major   Minor   RaidDevice State
+       0       8        1        0      active sync   /dev/sda1
+       1       0        0        1      removed
+}}}