Safety Engineer, Dad, Husband, Pilot, Musician. Not necessarily in that order.

Ingenieur für funktionale Sicherheit, Vater, Ehemann, Pilot, Musiker. Nicht notwendigerweise in dieser Reihenfolge.

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Joined 1 year ago
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Cake day: June 11th, 2023

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  • I also use this, and it works great. Another downside is that when using the free service, others can just use subdomains of your registered domains. You can always deny it, but you have to do it manually. With the premium subscriptions you can prevent that automatically for a number of domains, depending on how much you pay.


  • To add, unlike “traditional” RAID, ZFS is also a volume manager and can have an arbitrary number of dynamic “partitions” sharing the same storage pool (literally called a “pool” in zfs). It also uses checksumming to determine if data has been corrupted. On redundant setups it will then quietly repair the corrupted parts with the redundant information while reading.




  • Hopfgeist@feddit.deOPtoSelfhosted@lemmy.worldDifferent "geometries" for same disk model?
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    8 months ago

    Sure, SCSI disks will show their defective list (“primary defects”, as delivered by the factory, and grown defects, accumulated during use), and they all have a couple hundred primary defects. But I don’t see why that would affect the reported geometry, given that it is fictional, anway. And all disks have enough spare tracks to accommodate for the defects, and offer the specified full number of total sectors, even for long list of grown defects. Incidentally, all the 4TB disks are still “perfect” in that they have no grown defects.

    And yes, ever since LBA, nobody has used sectors and cylinders for anything.


  • I’m not touching that post again. But a small rant about typesetting in lemmy: It seems there is no way whatsoever to put angle brackets in a “code” section. In an overzealous attempt to prevent HTML injection, everything in angle brackets is just removed when posting (although it remains there in preview). In normal text, you can use “<”, but not inside “code” segments, where it will be retained verbatim.



  • If you’re as paranoid as me about data integrity, SAS drives on a host adapter card in “Initiator Target” (IT) mode with write-cache on the disks disabled is the safest. It will degrade performance when writing many small files concurrently, but not as badly as with SATA drives (that’s for spinning disks, of course, not SSD). With a good error-correcting redundant system such as ZFS you can probably get away with enabled write cache in most cases. Until you can’t.


  • RAID is generally a good thing but don’t get complacent, follow the 3-2-1 method

    To expand on that: Redundant drive setup and backups serve completely different purposes. The only overlap is in case of a single disk failure, where RAID (or similar) may save the data.

    Redundancy is all about reducing downtime in case of single hardware failures. Backups not only protect you from data loss in case of multiple simultaneous failures, but also from accidental deletion. Failures that require restoration of data almost always involve downtime. In short: You always need backups (unless it’s strictly a local cache, and easily recreatable), but if you want high availability, redundancy may help.

    3-2-1-rule for backups, in case you’re unfamiliar: 3 copies of important data, on 2 different media, with 1 off-site.


  • If you want a proper server, it seems that Asrock Rack is the only manufacturer of AM4-socket-based server mainboards. Unlike desktop/gamer boards, these are designed for parallel airflow, typically from front to back in a 19" rack. These also come with IPMI remote maintenance, so can be operated headless in a remote location.

    I have considered one of these for a while, such as the X570D4U, which also supports up to 128 GB of ECC RAM. Depending on what you want, this may be overkill, though.

    (This was my favourite, because it has two M.2 slots, but there are others with only a single slot, since you said you only need one.)

    Unlike gamer or other boards, these have no fancy black vanity covers and often won’t allow overclocking, but are typically very well designed and rock solid for unattended 24/7 operation.




  • Not so much server-based, but the experimental part of “lab” is well covered: I replaced my late-2013 27" iMac’s internal HDD with an SSD. It’s a really delicate procedure, as the display is glued to the chassis; it needs to be cut loose and very carefully removed (it’s tempered glass), and then re-glued with special adhesive strips. But the performance gain is worth it. In addition, it also now runs Ventura, even with the nVIDIA card, thanks to OpenCore Legacy Patcher. Feels like a new machine now, and is perfectly adequate even for small video editing tasks with its 32 GB RAM.


  • I don’t think there’s anything intrinsically wrong, but far as I can see you are using only a single disk for the zfs pool, which will give you integrity checks (know when something is corrupted), but no way to fix it.

    Since this is, by today’s standards, a tiny disk at 100G, I assume this is just a test setup? I’m not sure zfs is particularly well suited for virtual machines, I think it is better to have the host handle the physical data integrity by having the disk image on a zfs filesystem, or giving the VM a zfs volume (block device) directly.




  • What are the advantages of raid10 over zfs raidz2? It requires more disk space per usable space as soon as you have more than 4 disks, it doesn’t have zfs’s automatic checksum-based error correction, and is less resilient, in general, against multiple disk failures. In the worst case, two lost disks can mean the loss of the whole pack, whereas raidz2 can tolerate the loss of any 2 disks. Plus, with raid you still need an additional volume manager and filesystem.



  • Yes. I use a G7 N36L as an offsite-backup server in my second apartment. Works great with NetBSD and zfs, using rsnapshot to make remote backups every night.

    Since it is only active for an hour and a half each night, it is my only server to put the disks into powersave mode the rest of the time. Computing eprformance is so low that I don’t even run a folding@home client. It usually cannot finish any work package before the deadline.