Then why do you think manufacturers still list these failure rates (to be sure, it is marked as a limit, not an actual rate)? I’m not being sarcastic or facetious, but genuinely curious. Do you know for certain that it doesn’t happen regularly? During a scrub, these are the kinds of errors that are quietly corrected (althouhg the scrub log would list them), as they are during normal operation (also logged).

My theory is that they are being cautious and/or perhaps don’t have any high-confidence data that is more recent.

Bit error rates have barely improved since then. So the probability of an error whenr reading a substantial fraction of a disk is now higher than it was in 2013.

But as others have pointed out. RAID is not, and never was, a substitute for a backup. Its purpose is to increase availability. And if that is critical to your enterprise, these things need to be taken into account, and it may turn out that raidz1 with 8 TB disks is fine for your application, or it may not. For private use, I wouldn’t fret. but make frequent backups.

This article was not about total disk failure, but about the much more insidious undetected bit error.

Let’s do the math:

The error-reate of modern hard disks is usually on the order of one undetectable error per 1E15 bits read, see for example the data sheet for the Seagate Exos 7E10. An 8 TB disk contains 6.4E13 (usable) bits, so when reading the whole disk you have roughly a 1 in 16 chance of an unrecoverable read error. Which is ok with zfs if all disks are working. The error-correction will detect and correct it. But during a resilver it can be a big problem.

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.

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.

That’s a very narrow-minded view. I thought the same thing when the iPad was new. But I changed my mind.

Sitting on the sofa and watching movies or reading news is a good application, a laptop is too clunky for that, and a phone screen is too small.

Also use as an air-navigation device (not only) light aircraft, and replacement for paper charts in airline operations. There are many legitimate uses where tablets are exactly what you want. If it’s not for you, fine.

Thanks.

Thanks. Right now I’m away from the machine so can’t look, but I’ll keep an eye open for a T420 mainboard and a second CPU, then. It’ll still be a decent machine, I think, with two E5-2470 V2. DDR3 ECC-RAM is also dirt cheap these days.

Clearly you neither read my post nor looked into what the air baffle in the T320 actually looks like. So whats your point?

It’s much more than a fan shroud. It’s a baffle specifically designed to guide cooling air over the CPU heatsinks and the RAM modules. This kind of airflow design is very common in servers. I wouldn’t trust it without, especially since the CPU heatsinks have no dedicated fans, but rely on the aerodynamic functioning of the baffle.

And yes, I know they are very similar, in fact I am quite (but not absolutely) certain that they are identical except for the actual second CPU socket. It’s almost as if you didn’t read my post. Even the soldering points for the second CPU socket are there in the single-CPU T320. They certainly won’t have different PSU connectors. They even share part numbers for the case.

I’d have to check the baffle shape again. But thanks for the insight.

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.

One urgent thingis that the EU follow the UK in abandoning the ill-conceived “client-side scanning”, aka Chat-Control.

MigSu-24 bombers

There’s no such thing as a MiG-24. (MiG has only ever used odd-numbered model designations, though I don’t know why. But it’s one of the reasons why it was a safe bet for Top Gun to use “MiG-28”, being sure not to refer to any real aircraft, past, present or (probably) future.

I use the names of chemical elements, but with two twists: I assign them in the order in which they appear in the song “The Elements” by Tom Lehrer, and I use the German names. So I have (or had), among others, Wasserstoff, Sauerstoff, Stickstoff, etc …

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.

ZFS raidz1 or raidz2 on NetBSD for mass storage on rotating disks, journaled FFS on RAID1 on SSD for system disks, as NetBSD cannot really boot from zfs (yet).

ZFS because it has superior safeguards against corruption, and flexible partitioning; FFS because it is what works.

What’s your problem with DAVx^5? It’s completely and permanently free and fully-featured on f-droid. Only the PlayStore version costs money. The authors don’t want to make money, but motivate you to move away from Google infrastructure.

If you only need address/phone number sync, then nextcloud is probably overkill, but I use it, and it works great. Also for calendar sync and file storage.

(You don’t need to put the community name in the title, especially not with “@”, which signifies usernames. Communities are prefixed by “!”.)