Yet another win for Systemd.

    • StarDreamer@lemmy.blahaj.zoneEnglish
      171·
      11 months ago

      Worked in IT, target disk mode is a life saver when you have to recover data from a laptop with a broken screen/keyboard/bad ribbon cable and don’t want to take apart something held together by glue.

    • RaoulDook@lemmy.worldEnglish
      151·
      11 months ago

      It’s a nice feature. I used it a few times on old Macs with external FireWire hard drives for booting a different OS or troubleshooting.

      • ramble81@lemm.ee
        108·
        11 months ago

        “ via NVMe-TCP (in case you wonder what that is: it’s the new hot shit for exposing block devices over the network, kinda like iSCSI…”

        So….?

    • smo@lemmy.sdf.org
      19·
      11 months ago

      “target disk mode”, which this claims to be taking a lot of inspiration from, pretty much turns your computer into an external harddrive - so you can connect another machine to it for direct access. This appears to be trying to accomplish the same, but over the network.

      If you’ve ever stuffed up a machine so badly that the best idea you could come up with, was to take the harddrive out and work on it from another machine - this pretty much allows you to do that. But instead of taking the drive out and putting it an external drive enclosure, you just ask the stuffed up machine to act as the external drive enclosure.

      • FuckBigTech347@lemmygrad.ml
        1·
        11 months ago

        From what I understand it’s basically like a “thin client” type of thing where the client loads the Kernel from local storage up to a certain point and then boots into a rootfs that is somewhere else on a remote server.

          • FuckBigTech347@lemmygrad.ml
            2·
            11 months ago

            Similar but in this case the Linux Kernel/Init System act as the PXE firmware so you don’t need a TFTP Server to load initramfs and a Kernel image. And you don’t need a NFS or Samba server because the Server has the drive with the rootfs already exposed to the network.

          • yum13241@lemm.ee
            2·
            11 months ago

            Basically, your system, if asked to, will boot into a limited mode where it exposes its drives over NVMe-TCP. It’s like taking the hard drive out and putting it into a different PC, but over the network.

        • winterayars@sh.itjust.works
          16·
          11 months ago

          A service by itself shouldn’t be systemd, it should be implemented separately and run under systemd. However, this is using the systemd target subsystem which is a little more specific.

          • immibis@social.immibis.com
            1·
            11 months ago

            @winterayars systems targets were formerly known as runlevels, and this particular one probably could also work with init= because what else could you possibly run at the same time?

                • winterayars@sh.itjust.works
                  4·
                  11 months ago

                  “You might be able to get away without systemd” does not mean there’s no benefit to using it. There could be a management benefit (easily putting the system in different states) and/or it may be (considerably) easier to do it with systemd baking it.

                  If you had to (hypothetically) reimplement most of systemd’s core functionally to do it without and can do it trivially with then that sounds like you don’t like “the project named systemd”, an opinion that should not have an impact on the technical decisions.

                  (Edit)

                  Actually i didn’t throw in any specific reasons that respond to the question itself. Let me do that.

                  This feature is leaning on connecting the storage through networking, which makes sense. (Ideally you would do it like macOS and only let direct computer-to-computer connection run it for security reasons, at least by default.) That means you need a DHCP stack spun up, which systemd gives the project an easy way to do. In addition, any other features can also lean on other pieces of the OS through systemd. It’s just easier.

                  Lennart Poettering, being a lead on the systemd project, is targeting systems where systemd is the init system. That is, it’s the first actual OS process started. With this in mind, if you wanted to start this “storage target mode” before systemd you would have to implement a bunch of stuff, ex a custom DHCP configuration to get networking going. Then, of course, you have the systemd “OS level” networking and then, separately, the “storage target mode” networking–which may mean you have to then implement UI to connect the device to the network if you have a special network configuration.

                  If you wanted to set this up after the init system then… uh… well, that’s the implementation as it currently is being developed. It’s a systemd target because systemd is the init system in question. That’s what Poettering is doing, here.

                  There are probably more reasons why it makes sense to use systemd, but fundamentally systemd is the init system and it can solve problems for the project.

      • patatahooligan@lemmy.world
        12·
        11 months ago

        How is it related? Is there something preventing the executable from running without systemd? Just providing a service and target file doesn’t mean anything if it can run without them just fine. If it came with a reference init script instead I don’t think people would be arguing that it’s part of sysvinit and that sysvinit is bloated.

  • signofzeta@lemmygrad.mlEnglish
    6·
    11 months ago

    How do you think file systems would be handled? Apple’s SCSI/FireWire/USB/Thunderbolt Target Disk Mode just made all disks available over the interface in a filesystem-agnostic manner. Would I be able to see my ext4 boot partition, ZFS arrays, and any attached volumes?

    • emptiestplace@lemmy.ml
      2·
      11 months ago

      As with Apple’s implementation, filesystems aren’t handled - whatever device you connected with would see block devices, essentially no different from a physical disk in your system.

  • andruid@lemmy.ml
    4·
    11 months ago

    So this is a service aimed at exposing disks as nvme-tcp boot targets on boot of the system? I mean I love it, I wonder if this could be used to help with a chicken and egg problem I’ve had with building clustered systems easier. So far I either need a running service to host a network file system (like NFS or CEPH), or I need local disks that bootstrap the clustered storage environment.

  • lambalicious@lemmy.sdf.orgEnglish
    11·
    11 months ago

    And why would this need systemd of all things? Should basically be doable over something like SSH / TFTP, right?

  • z3rOR0ne@lemmy.ml
    1118·
    11 months ago

    Not compelling to me. Gonna stick with runit and/or s6 on my Artix Linux systems at home. But you do you Lennart.