{"id":2416,"date":"2016-07-07T22:21:16","date_gmt":"2016-07-07T10:21:16","guid":{"rendered":"http:\/\/www.zoyinc.com\/?p=2416"},"modified":"2023-05-28T16:39:56","modified_gmt":"2023-05-28T04:39:56","slug":"backing-up-open-media-vault","status":"publish","type":"post","link":"http:\/\/www.zoyinc.com\/?p=2416","title":{"rendered":"Backing up Open Media Vault"},"content":{"rendered":"

Backing up OMV can be a challenge as it doesn’t have any backup functionality. While there are solutions like Clonezilla and rsync the simplest is “dd” or “dcfldd”. You should read the article Installing Open Media Vault<\/a> which explains how I suggest you do it so you don’t have to backup a 250GB hard drive.<\/p>\n

This post describes backing up and restoring in a scenario where OMV is installed to a very small, 7GB, portion of the system disk. Again the article\u00a0Installing Open Media Vault<\/a> describes this approach in more detail<\/p>\n

Before you start<\/h2>\n

Before you do anything I would suggest you remove any drives you don’t need. So if restoring from RAID then obviously you need the RAID disks. But if you are restoring from a network share then all you need is the system disk connected. It’s just about being extra careful that you don’t accidentally wipe over the wrong thing.<\/p>\n

For this exercise we will boot from a Debian USB so follow the instructions in the post Create a Debian Live USB flash drive<\/a><\/p>\n

We are going to use “dcfldd” so you should install it:<\/p>\n

apt-get install dcfldd<\/pre>\n
Note the above might appear to hang on “processing triggers for man-db”, just be patient it might take a minute or so.<\/p>\n
Wipe the disk first<\/h3>\n
Sometimes its a good idea to wipe out the new disk first, if you want to do this follow the instructions in the post\u00a0Wipe a RAID disk.<\/p>\n
First work out which disk needs to be wiped by running “lsblk”:<\/p>\n
root@debian:~# lsblk\nNAME\u00a0\u00a0 MAJ:MIN RM\u00a0 SIZE RO TYPE MOUNTPOINT\nsda\u00a0\u00a0\u00a0\u00a0\u00a0 8:0\u00a0\u00a0\u00a0 1\u00a0 7.5G\u00a0 0 disk\n\u2514\u2500sda1\u00a0\u00a0 8:1\u00a0\u00a0\u00a0 1\u00a0 1.2G\u00a0 0 part \/lib\/live\/mount\/medium\nsdb\u00a0\u00a0\u00a0\u00a0\u00a0 8:16\u00a0\u00a0 0 55.9G\u00a0 0 disk\n\u251c\u2500sdb1\u00a0\u00a0 8:17\u00a0\u00a0 0 53.6G\u00a0 0 part\n\u251c\u2500sdb2\u00a0\u00a0 8:18\u00a0\u00a0 0\u00a0\u00a0\u00a0 1K\u00a0 0 part\n\u2514\u2500sdb5\u00a0\u00a0 8:21\u00a0\u00a0 0\u00a0 2.3G\u00a0 0 part\nloop0\u00a0\u00a0\u00a0 7:0\u00a0\u00a0\u00a0 0\u00a0 1.1G\u00a0 1 loop \/lib\/live\/mount\/rootfs\/filesystem.squashfs<\/pre>\n
From the above you can see sda is the Debian Live USB key and loop is part of this.<\/p>\n
Thus we can see that sdb with 3 partitions is the system drive. If you want to zero the entire drive drive as well to reduce your backup sizes then run the following:<\/p>\n
dcfldd if=\/dev\/zero of=\/dev\/sdb<\/pre>\n
Giving you something like:<\/p>\n
root@debian:~# dcfldd if=\/dev\/zero of=\/dev\/sdb\n47616 blocks (1488Mb) written.<\/pre>\n
And results in<\/p>\n
root@debian:~# dcfldd if=\/dev\/zero of=\/dev\/sdb\n2441984 blocks (76312Mb) written.\n2442211+0 records in\n2442210+0 records out<\/pre>\n
If you wanted to zero a smaller section of the disk you would run something like:<\/p>\n
dcfldd if=\/dev\/zero of=\/dev\/sdb bs=512 count=15682111<\/pre>\n
This will zero 15682111 sectors each sector being 512 bytes<\/p>\n
Mount the restore location<\/p>\n
Now make the image restore\/backup accessible.<\/p>\n
Backup to a shared network drive<\/h3>\n
If the backup image is on a shared network drive then map this to a mount point:<\/p>\n
mkdir \/nas1\nmount -t cifs -o username=joe,password=joesPassword \/\/192.168.202.44\/sata1 \/nas1\ncd \/nas1<\/pre>\n
If you get an error “Host is down” you might need to add “vers=1.0” or similar. This would give:<\/p>\n
mount -t cifs -o vers=1.0,username=joe,password=joesPassword \/\/192.168.202.44\/sata1 \/nas1<\/pre>\n
Backup to a local RAID array<\/h3>\n
If the backup image is on the RAID drive for OMV then you need to first install the mdadm packages:<\/p>\n
apt-get install mdadm rsync initramfs-tools<\/pre>\n
During the install it will ask about “Configuring mdadm” and will ask about “MD arrays needed for the root file system”. You need to enter “none” as your answer and click <enter>.<\/p>\n
There is another issue at this point and that is if the terminal window, Putty say, is too small then all you see will be:\"mdadmIf you see this then close your terminal\/Putty session and start again – using <ctrl>C doesn’t work. You should instead see:<\/p>\n
\"mdadm<\/a>
+ Click to enlarge<\/figcaption><\/figure>\n
So at this stage enter “none” and press <enter> to continue.<\/p>\n
Now run “lsblk” to see what filesystems and RAID arrays exist on your system:<\/p>\n
root@debian:~# lsblk\nNAME\u00a0\u00a0\u00a0 MAJ:MIN RM\u00a0 SIZE RO TYPE\u00a0 MOUNTPOINT\nsda\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:0\u00a0\u00a0\u00a0 0 74.5G\u00a0 0 disk\n\u251c\u2500sda1\u00a0\u00a0\u00a0 8:1\u00a0\u00a0\u00a0 0\u00a0 9.6G\u00a0 0 part\n\u251c\u2500sda2\u00a0\u00a0\u00a0 8:2\u00a0\u00a0\u00a0 0\u00a0\u00a0\u00a0 1K\u00a0 0 part\n\u2514\u2500sda5\u00a0\u00a0\u00a0 8:5\u00a0\u00a0\u00a0 0\u00a0 466M\u00a0 0 part\nsdb\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:16\u00a0\u00a0 0 74.5G\u00a0 0 disk\n\u2514\u2500md127\u00a0\u00a0 9:127\u00a0 0 74.5G\u00a0 0 raid1\nsdc\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:32\u00a0\u00a0 0 74.5G\u00a0 0 disk\n\u2514\u2500md127\u00a0\u00a0 9:127\u00a0 0 74.5G\u00a0 0 raid1\nsdd\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:48\u00a0\u00a0 1\u00a0 7.5G\u00a0 0 disk\n\u2514\u2500sdd1\u00a0\u00a0\u00a0 8:49\u00a0\u00a0 1\u00a0 1.2G\u00a0 0 part\u00a0 \/lib\/live\/mount\/medium\nloop0\u00a0\u00a0\u00a0\u00a0 7:0\u00a0\u00a0\u00a0 0\u00a0 1.1G\u00a0 1 loop\u00a0 \/lib\/live\/mount\/rootfs\/filesystem.squashfs<\/pre>\n
From the above you can see the array is “md127” so create a mount point and mount the array:<\/p>\n
mkdir \/raid\nmount \/dev\/md127 \/raid<\/pre>\n
Doing a backup<\/h2>\n
For this example we will backup to a local RAID array.<\/p>\n
Lets look at lsblk again:<\/p>\n
root@debian:\/# lsblk\nNAME\u00a0\u00a0\u00a0 MAJ:MIN RM\u00a0 SIZE RO TYPE\u00a0 MOUNTPOINT\nsda\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:0\u00a0\u00a0\u00a0 0 74.5G\u00a0 0 disk\n\u251c\u2500sda1\u00a0\u00a0\u00a0 8:1\u00a0\u00a0\u00a0 0\u00a0 6.7G\u00a0 0 part\n\u251c\u2500sda2\u00a0\u00a0\u00a0 8:2\u00a0\u00a0\u00a0 0\u00a0\u00a0\u00a0 1K\u00a0 0 part\n\u2514\u2500sda5\u00a0\u00a0\u00a0 8:5\u00a0\u00a0\u00a0 0\u00a0 341M\u00a0 0 part\nsdb\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:16\u00a0\u00a0 0 74.5G\u00a0 0 disk\n\u2514\u2500md127\u00a0\u00a0 9:127\u00a0 0 74.5G\u00a0 0 raid1 \/raid\nsdc\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:32\u00a0\u00a0 1\u00a0 7.5G\u00a0 0 disk\n\u2514\u2500sdc1\u00a0\u00a0\u00a0 8:33\u00a0\u00a0 1\u00a0 1.2G\u00a0 0 part\u00a0 \/lib\/live\/mount\/medium\nloop0\u00a0\u00a0\u00a0\u00a0 7:0\u00a0\u00a0\u00a0 0\u00a0 1.1G\u00a0 1 loop\u00a0 \/lib\/live\/mount\/rootfs\/filesystem.squashfs<\/pre>\n
So from the above we can see that the system drive is sda. You can also look at the disk sizes as this may give you a clue. Lets look at sda and run fdisk:<\/p>\n
root@debian:\/# fdisk -l \/dev\/sda\n\nDisk \/dev\/sda: 74.5 GiB, 80026361856 bytes, 156301488 sectors\nUnits: sectors of 1 * 512 = 512 bytes\nSector size (logical\/physical): 512 bytes \/ 512 bytes\nI\/O size (minimum\/optimal): 512 bytes \/ 512 bytes\nDisklabel type: dos\nDisk identifier: 0x00080b9b\n\nDevice\u00a0\u00a0\u00a0\u00a0 Boot\u00a0\u00a0\u00a0 Start\u00a0\u00a0\u00a0\u00a0\u00a0 End\u00a0 Sectors\u00a0 Size Id Type\n\/dev\/sda1\u00a0 *\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 2048 13977599 13975552\u00a0 6.7G 83 Linux\n\/dev\/sda2\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 13979646 14678015\u00a0\u00a0 698370\u00a0 341M\u00a0 5 Extended\n\/dev\/sda5\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 13979648 14678015\u00a0\u00a0 698368\u00a0 341M 82 Linux swap \/ Solaris<\/pre>\n
So you can see that the partitions which are actively used go from 0 to 14678015 sectors and the sectors are 512 bytes.<\/p>\n
So I will suggest you copy an extra 4096 bytes, just to be safe \ud83d\ude42 so in our case this is:<\/p>\n
14678015 + 4096 = 14682111<\/p>\n
So do a backup by running:<\/p>\n
dcfldd bs=512 count=14682111 if=\/dev\/sda | gzip -c > \/raid\/backups\/nas2_10-7-2016_512k-blocks.img.gz<\/pre>\n
Note you should set the block size, “bs=” in dcfldd to match what fdisk reports, in this case 512. At the end you should see:<\/p>\n
root@debian:\/raid#\u00a0 dcfldd bs=512 count=14682111 if=\/dev\/sda | gzip -c > \/raid\/backups\/nas2_10-7-2016_512k-blocks.img.gz\n14681856 blocks (7168Mb) written.\n14682111+0 records in\n14682111+0 records out<\/pre>\n
For a 7GB disk this should take say 5 – 10 minutes but not hours!<\/p>\n
Doing a restore<\/h2>\n
Lets look at lsblk again:<\/p>\n
root@debian:\/raid\/backups# lsblk\nNAME\u00a0\u00a0\u00a0 MAJ:MIN RM\u00a0 SIZE RO TYPE\u00a0 MOUNTPOINT\nsda\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:0\u00a0\u00a0\u00a0 1\u00a0 7.5G\u00a0 0 disk\n\u2514\u2500sda1\u00a0\u00a0\u00a0 8:1\u00a0\u00a0\u00a0 1\u00a0 1.2G\u00a0 0 part\u00a0 \/lib\/live\/mount\/medium\nsdb\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:16\u00a0\u00a0 0 55.9G\u00a0 0 disk\nsdc\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 8:32\u00a0\u00a0 0 74.5G\u00a0 0 disk\n\u2514\u2500md127\u00a0\u00a0 9:127\u00a0 0 74.5G\u00a0 0 raid1 \/raid\nloop0\u00a0\u00a0\u00a0\u00a0 7:0\u00a0\u00a0\u00a0 0\u00a0 1.1G\u00a0 1 loop\u00a0 \/lib\/live\/mount\/rootfs\/filesystem.squashfs<\/pre>\n
So from the above we can see that the system drive is sdb because sda with the “\/lib\/live\/mount”.\u00a0 is Debian Live and sdc is the RAID disk.<\/p>\n
You can also look at the disk sizes as this may give you a clue.<\/p>\n
First run “fdisk -l” against your disk to work out the block size:<\/p>\n
root@debian:\/raid\/backups# fdisk -l \/dev\/sdb\n\nDisk \/dev\/sdb: 55.9 GiB, 60011642880 bytes, 117210240 sectors\nUnits: sectors of 1 * 512 = 512 bytes\nSector size (logical\/physical): 512 bytes \/ 512 bytes\nI\/O size (minimum\/optimal): 512 bytes \/ 512 bytes<\/pre>\n
So from the above you can see that for “dev\/sdb” the block size is 512<\/p>\n
Start the restore by running something like:<\/p>\n
gunzip -c \/raid\/backups\/nas2_10-7-2016_512k-blocks.img.gz | dcfldd bs=512 of=\/dev\/sdb<\/pre>\n
This will return:<\/p>\n
root@debian:\/nas1# gunzip -c \/nas1\/omv2.1_vanilla_7gb-hdd_2-7-2016_512k-blocks.img.gz | dcfldd bs=512 of=\/dev\/sda\n14680064 blocks (7168Mb) written.\n14680064+0 records in\n14680064+0 records out<\/pre>\n
So you can see the records count matches and all is good.<\/p>\n","protected":false},"excerpt":{"rendered":"
Backing up OMV can be a challenge as it doesn’t have any backup functionality. While there are solutions like Clonezilla and rsync the simplest is “dd” or “dcfldd”. You should read the article Installing Open Media Vault which explains how I suggest you do it so you don’t have to backup a 250GB hard drive. […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2416","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=\/wp\/v2\/posts\/2416","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2416"}],"version-history":[{"count":20,"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=\/wp\/v2\/posts\/2416\/revisions"}],"predecessor-version":[{"id":5262,"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=\/wp\/v2\/posts\/2416\/revisions\/5262"}],"wp:attachment":[{"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2416"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2416"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.zoyinc.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2416"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}