[[PageOutline]] * verbose log of [../] = mdadm -D /dev/md0 = * mitty@ubuntu-haa:~$ sudo mdadm -D /dev/md0 {{{ /dev/md0: Version : 00.90 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 : 2 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Thu Mar 24 17:31:47 2011 State : clean Active Devices : 2 Working Devices : 2 Failed Devices : 0 Spare Devices : 0 UUID : 32578407:6f33f50b:893cf340:745f5dce (local to host ubuntu-haa) Events : 0.34 Number Major Minor RaidDevice State 0 8 17 0 active sync /dev/sdb1 1 8 33 1 active sync /dev/sdc1 }}} = dpkg-reconfigure mdadm = * see also wiki:TipAndDoc/RAID#dpkg-reconfiguremdadm * mitty@ubuntu-haa:~$ sudo dpkg-reconfigure mdadm {{{ ┌──────────────────────────┤ Configuring mdadm ├─ │ │ │ If the kernel supports it (versions greater than 2.6.14), mdadm can │ │ periodically check the redundancy of MD arrays (RAIDs). This may be a │ │ resource-intensive process, depending on the local setup, but it could │ │ help prevent rare cases of data loss. Note that this is a read-only │ │ check unless errors are found; if errors are found, mdadm will try to │ │ correct them, which may result in write access to the media. │ │ │ │ The default, if turned on, is to check on the first Sunday of every │ │ month at 01:06. │ │ │ │ Should mdadm run monthly redundancy checks of the MD arrays? │ │ │ │ [[]] │ │ │ └────────────────────────────────────── (snip) ┌──────────────────────────┤ Configuring mdadm ├─ │ │ │ The MD (RAID) monitor daemon sends email notifications in response to │ │ important MD events (such as a disk failure). │ │ │ │ Enabling this option is recommended. │ │ │ │ Do you want to start the MD monitoring daemon? │ │ │ │ [[]] │ │ │ └────────────────────────────────────── (snip) ┌─────────────────────────┤ Configuring mdadm ├── │ Please enter the email address of the user who should get the email │ │ notifications for important MD events. │ │ │ │ Recipient for email notifications: │ │ │ │ root_________________________________________________________________ │ │ │ │ │ │ │ └─────────────────────────────────────── (snip) ┌───────────────────────────┤ Configuring mdadm ├ │ │ │ If your root filesystem is on a RAID, and a disk is missing at boot, it │ │ can either boot with the degraded array, or hold the system at a │ │ recovery shell. │ │ │ │ Running a system with a degraded RAID could result in permanent data │ │ loss if it suffers another hardware fault. │ │ │ │ If you do not have access to the server console to use the recovery │ │ shell, you might answer "yes" to enable the system to boot unattended. │ │ │ │ Do you want to boot your system if your RAID becomes degraded? │ │ │ │ [[]] │ │ │ └─────────────────────────────────────── }}} = pvcreate /dev/md0 = * mitty@ubuntu-haa:~$ sudo pvcreate /dev/md0 {{{ Physical volume "/dev/md0" successfully created }}} * mitty@ubuntu-haa:~$ sudo pvdisplay -C {{{ PV VG Fmt Attr PSize PFree /dev/md0 lvm2 -- 1.95g 1.95g }}} * mitty@ubuntu-haa:~$ sudo pvdisplay {{{ "/dev/md0" is a new physical volume of "1.95 GiB" --- NEW Physical volume --- PV Name /dev/md0 VG Name PV Size 1.95 GiB Allocatable NO PE Size 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID Z2JXRP-fa5g-SYS5-xzMs-Lq8C-1Jbh-QPKihr }}} = vgcreate -s 32 vgnfs /dev/md0 = * mitty@ubuntu-haa:~$ sudo vgcreate -s 32 vgnfs /dev/md0 {{{ Volume group "vgnfs" successfully created }}} * mitty@ubuntu-haa:~$ sudo vgdisplay -C {{{ VG #PV #LV #SN Attr VSize VFree vgnfs 1 0 0 wz--n- 1.94g 1.94g }}} * mitty@ubuntu-haa:~$ sudo vgdisplay {{{ --- Volume group --- VG Name vgnfs System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 1 VG Access read/write VG Status resizable MAX LV 0 Cur LV 0 Open LV 0 Max PV 0 Cur PV 1 Act PV 1 VG Size 1.94 GiB PE Size 32.00 MiB Total PE 62 Alloc PE / Size 0 / 0 Free PE / Size 62 / 1.94 GiB VG UUID I6vVoh-6gCJ-9uvA-v2MV-Fyva-7J8v-Cvftfi }}} * mitty@ubuntu-haa:~$ sudo pvdisplay -C {{{ PV VG Fmt Attr PSize PFree /dev/md0 vgnfs lvm2 a- 1.94g 1.94g }}} * mitty@ubuntu-haa:~$ sudo pvdisplay {{{ --- Physical volume --- PV Name /dev/md0 VG Name vgnfs PV Size 1.95 GiB / not usable 15.94 MiB Allocatable yes PE Size 32.00 MiB Total PE 62 Free PE 62 Allocated PE 0 PV UUID Z2JXRP-fa5g-SYS5-xzMs-Lq8C-1Jbh-QPKihr }}}