md array setup

  • I am new to OMV. I have version 7.4.6-1 installed on an M.2 SATA SSD drive in an old Lenovo i5 system with 16GB of RAM and two 2TB HDDs.

    I installed the recommended plugins + a few others. I did this 1 month ago so my memory is a bit fuzzy.

    I looked at the documentation, but don't see much for how to setup an MD RAID array. Where to start? Is it only possible from the command line or is there a GUI for creation? I want to setup the 2TB drives in a RAID 0 mode.

    PS: just discovered LVM2 can create an MD array, according to this. My use of LVM has always been from command line. I am comfortable on cmd line but prefer GUI for ease of use. Is LVM the best way to setup storage with MD under OMV?

    Edited once, last by nasadmin: Added OMV version, LVM comments ().

    • Official Post

    No need to use LVM. On OMV 7, just install the openmediavault-md plugin to be able to create the mdadm array.

    omv 7.4.10-1 sandworm | 64 bit | 6.8 proxmox kernel

    plugins :: omvextrasorg 7.0 | kvm 7.0.14 | compose 7.2.14 | k8s 7.3.1-1 | cputemp 7.0.2 | mergerfs 7.0.5 | scripts 7.0.9


    omv-extras.org plugins source code and issue tracker - github - changelogs


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  • It is installed, so now what? I don't see anything in the GUI about using it. When I look at the stuff under the main Storage section in the left nav there are no arrays defined. How do they get defined?

    Under the LVM section, Physical Volumes, clicking the + to Create, it provides no devices to select, although there are 2 uninitialized drives that should show up.

    • Official Post

    You have to create an array using the plugin. The plugin expects the arrays to be wiped.


    Do you really need raid? I tell most people to create an ext4 filesystem on both drives and schedule an rsync job to sync one drive to the other.

    omv 7.4.10-1 sandworm | 64 bit | 6.8 proxmox kernel

    plugins :: omvextrasorg 7.0 | kvm 7.0.14 | compose 7.2.14 | k8s 7.3.1-1 | cputemp 7.0.2 | mergerfs 7.0.5 | scripts 7.0.9


    omv-extras.org plugins source code and issue tracker - github - changelogs


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  • You have to create an array using the plugin. The plugin expects the arrays to be wiped.


    Do you really need raid? I tell most people to create an ext4 filesystem on both drives and schedule an rsync job to sync one drive to the other.

  • That's not a bad alternative, I'll investigate the pros & cons of that approach. My gut says since rsync works at a much higher level than MD, that when a drive fails the destination might end up in a weird state, whereas MD would avoid that. Also, read performance my not be as good, although the difference is not likely to be significant or of concern.

    However, I don't see anything in the GUI to "operate" the plugin. I can see the status of all plugins under the System--> Plugins in left nav, but nothing else. Would you please be more specific on how I access plugin functionality?

    Thank you

    • Official Post

    I don't see anything in the GUI to "operate" the plugin. I can see the status of all plugins under the System--> Plugins in left nav, but nothing else. Would you please be more specific on how I access plugin functionality?

    If you installed the plugin from the Plugins tab, you should see a "Multiple Device" tab in the Storage section.

    That's not a bad alternative, I'll investigate the pros & cons of that approach. My gut says since rsync works at a much higher level than MD, that when a drive fails the destination might end up in a weird state, whereas MD would avoid that. Also, read performance my not be as good, although the difference is not likely to be significant or of concern.

    If you are worried about that, then use something like rsnapshot or borgbackup (I use borg) to have many copies. Since the deduplicate, additional backups take very little space. They are better for accidental deletions/ransomware as well. All actions on a raid 1 mirror are instant. And if your array fails to assemble, it is possible you could lose the data on both drives.


    With old drives like that, I doubt the read performance will be much different. And unless you have something faster than gigabit networking, it won't matter.

    omv 7.4.10-1 sandworm | 64 bit | 6.8 proxmox kernel

    plugins :: omvextrasorg 7.0 | kvm 7.0.14 | compose 7.2.14 | k8s 7.3.1-1 | cputemp 7.0.2 | mergerfs 7.0.5 | scripts 7.0.9


    omv-extras.org plugins source code and issue tracker - github - changelogs


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  • One of the 2 HDD drives are old, the other I just bought for the MD mirror.

    I do not see a "Multiple Device" items under storage, b/c I didn't install it! Doh!!!

    Forgive me, it's been a month since I set this up. I thought I installed it, and when I went to the System--> plugins I saw it in the list and assumed it was installed. Now I see the plugins that are installed are clearly marked.

    I do seem to recall the plugin for reducing the load on USB boot devices is not in the list, and is from a 3rd party, is that right?

    If so, how are such plugins installed?

    Now that it's installed I see the "Multiple Device" item, however when I click it and select the + and set type to mirror no disks show up, even tho they do under the Storage--> disks.

    Also, I added a user to the _ssh and sudo groups, who can now ssh in but has no sudo priviledges. When I look at that user's info in the GUI it looks correct and it's applied. However there are no entries in the /etc/sudoers file or the sudoers.d folder.

  • Now that it's installed I see the "Multiple Device" item, however when I click it and select the + and set type to mirror no disks show up, even tho they do under the Storage--> disks.

    if there are partitions of filesystems on them, you first need to erase the disks.

    (button in storage / disks)

    Then they should show up...

    Qnap TS-853A

    Syno DS-1618+

    Qnap TS-451+

    Qnap TS-259 Pro+

  • They both had an empty GPT partition table, no partitions defined. I used fdisk /dev/sdaX -w, used the w command to save to disk then I exited fdisk. Still no sign of the drives under multiple disks create after selecting mirror mode.

  • They both had an empty GPT partition table, no partitions defined. I used fdisk /dev/sdaX -w, used the w command to save to disk then I exited fdisk. Still no sign of the drives under multiple disks create after selecting mirror mode.

    Wipe them. It uses the wipefs command. A quick wipe is usually enough.

    • Official Post

    I do seem to recall the plugin for reducing the load on USB boot devices is not in the list, and is from a 3rd party, is that right?

    If so, how are such plugins installed?

    install omv-extras then the flashmemory plugin.

    omv 7.4.10-1 sandworm | 64 bit | 6.8 proxmox kernel

    plugins :: omvextrasorg 7.0 | kvm 7.0.14 | compose 7.2.14 | k8s 7.3.1-1 | cputemp 7.0.2 | mergerfs 7.0.5 | scripts 7.0.9


    omv-extras.org plugins source code and issue tracker - github - changelogs


    Please try ctrl-shift-R and read this before posting a question.

    Please put your OMV system details in your signature.
    Please don't PM for support... Too many PMs!

  • Ok, I used the wipefs command and that resolved the drives not showing up under Storage--> Multiple Drives--> Create.
    After resuming from suspend last night the sudo command now works as well.

    ryecoaaron - you said what to install but now how to install it, but I found out how so no worries.

    Last issue is for the WeTTY plugin. After installing it and going to the Services--> WeTTY to change the port, I get a server 500 error when I try to enable the plugin. I also tried to create a certificate which succeeded but still couldn't enable the service.

  • Last issue is for the WeTTY plugin. After installing it and going to the Services--> WeTTY to change the port, I get a server 500 error when I try to enable the plugin. I also tried to create a certificate which succeeded but still couldn't enable the service.

    Post your 500 error. When you get it, go th the bell icon in the top right and copy to clipboard. Then paste the text in your reply. The answer to the problem is usually in that error, but all the information is not displayed in the red on-screen box.

  • There's nothing to post. When I go to the notifications it just shows the 500 error, and when I click on the 3 vertical dots the "save to clipboard" option isn't active. Is there a log file I can grab it from, or is it under journalctl? I just looked and don't see anything related to WeTTY or thhe port I used in the journal. Oh, just realized it's a web server error. I'll check under nginx...

    All I see in the /var/log/nginx/openmediavaullt-webgui_access.log are tons of 500 errors and 200s from Monit, so no help from that, unless it's caused by the browser version which seems highly unlikely.

    I got the omv extras plugin installed, and also the docker compose plugin it said to install. Not sure how to setup that compose plugin tho. I have used both docker & compose, but it's been awhile and I never got into compose very deeply, mostly just used what others created for the project.

  • Have you tried a browser cache refresh? Ctrl-shift-r, cmd-shift-r, or ctrl-shift-click reload depending on the os and/or browser.


    Someone else may be able to help you better parsing logs. It’s not something I have a lot of experience doing, as I rarely have an error requiring it.

  • Ok, lucky you!

    A server error (500) isn't going to be resolved with a browser cache reload. Besides, there's nothing in the browser cache for that port yet, until the server responds to the browser request.

    Thanks just the same, and for your help with the other matters.

    Greatly appreciated!

  • 500 errors with OMV are sometimes solved by that because the browser cache is using old data. It has been seen on the forum many rimes and is part of the posted common problems fixes. Doing what I said is not dumping all cache, it us just telling browser to re-cache fresh data from that page.

  • for reference


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