"Also, having the garage open/door unlock as you pull up feels like magic, and I never get tired of it."
I pull into my driveway, press a button on a $15 remote, and the garage door is opened by a thing that is worth about $200. Nothing "smart" about it, and hard to see how being "smart" would improve it.
I get that some people seem to like the idea, but I have just never really understood the appeal of "smart home" stuff. I mean, "for the low, low price of several thousand dollars, we can make it so you don't have to flip light switches anymore!" is just really not an appealing offer. Flipping light switches is not a problem.
It's just 1 more thing I don't think about. Like walking up to my car and it auto-unlocking when I put my hand on the handle. As I pull up to my house, the garage is opening and I pull right in. Same with auto-locking the door, I just close it and it will lock behind me. I like little bits of "magic" sprinkled into my day.
"I often experience this. I saw that a co worker had written something about God in their Twitter bio. 'Are you a Christian?' 'I'm a Catholic' they replied. Any other denomination would say 'yes I'm a Christian'"
I'm going to suggest that if you would find it surprising to have your question answered with "Yes, Greek Orthodox," or "Yes, Southern Baptist," or "Yes, United Methodist," or some similar variation, your personal experience may not be as broad or definitive as you seem to think it is.
Well it's a common question I've asked of people during my life, and only catholics ever make that distinction, almost a correction. And there's a reason why - because they think it's the one true church.
I'm not in the USA btw.
OK. I'm curious, roughly where are you? And if non-denominational, sort of generic "Christians" are common there now, what was the situation historically?
I'm in the UK.
Normal conversation: what did you do on Sunday? I was in church. "Oh are you a Christian" "yes".
Now, if the first person is not a Christian , that's often the end of the conversation.
If first person is also a Christian they would say "oh me too! What sort of church do you go to".
They might then answer, oh I got to st Luke's, have you heard of it. Or I go to so and so in the town. The baptist church? Yeah that one"
It's very unusual for a non Catholic to go straight to denominations in answer to the "are you a Christian", because that's not the question, and due to the appeal to unity, because of the belief that we're all part of god's family, rather than go straight for dividing lines. And never would anyone identify as "I'm a protestant", that would be odd.
OK thanks. By the UK, do you mean Great Britain? England? Something else?
As far as I know (admittedly not far), Christians in the UK are about one-third Church of England, one-third non-denominational, one-fifth Catholic, and the rest other. I think most of the growth in non-denominational Christian churches in the UK has taken place in my lifetime.
There is a particular part of the UK where, in fairly recent decades, I think self-identifying as "Protestant," as quite specifically opposed to "Catholic," was not at all odd, to use your word. Not sure of the extent to which that's still the case.
Can't speak for anyone else, but it is not unusual (nor new) for someone to describe themselves as "Catholic." Briefly, they usually mean that they are a member of the Roman Catholic Church. Wikipedia will provide a great deal of reading about it.
Neither is it unusual for someone to describe themselves as a particular Protestant denomination: Lutheran, Baptist, Methodist, Presbyterian, Episcopalian, et al. Again, Wikipedia is a good starting place.
People who simply describe themselves as "Christian" are what, in my experience at least, is relatively new. Going back, say, fifty years, it was somewhat unusual in many parts of the US to find people who described themselves that way.
In my experience, most of these people belong to one or another of what might be called non-denominational Christian churches. My preferred term for many of them is "contemporary American fundamentalist Christian," but that is not a widely used term, at least not that I know of.
Your question is strange enough that I'm honestly not sure whether or not you're trolling. If you are, as it seems you might be, a member of a contemporary American non-denominational Christian church, it is very weird, whether you know it or not, to suggest that a church that has existed for roughly two thousand years and has many more than a billion members wordwide is "splintering off" and "making [its] own religion."
FWIW, this is what Gemini thinks you are likely doing. Is this correct, or close?
The Trick: The "Sparse File" Loopback
Since ZFS doesn't allow you to convert a single disk vdev to RAID-Z1, Umbrel's "FailSafe" mode almost certainly uses a sparse file to lie to the system.
Phase 1 (Single Drive): When you set up Umbrel with one 2TB SSD, they don't just create a simple ZFS pool. They likely create a RAID-Z1 pool consisting of your physical SSD and two "fake" virtual disks (large files on the same SSD).
The "Degraded" State: They immediately "offline" or "remove" the fake disks. The pool stays in a DEGRADED state but remains functional. To you, the UI just shows "1 Drive."
Phase 2 (Adding the 2nd Drive): When you plug in the second drive, umbrelOS likely runs a zpool replace command, replacing one of those "fake" virtual disks with your new physical SSD.
Resilvering: ZFS then copies the parity data onto the second disk.
Great question! Close, but not exactly. We do use a sparse file but only very briefly during the transition.
We start with 1 SSD as a single top level vdev. When you add the second SSD you choose if you want to enable FailSafe or not. If you don't enable FailSafe you can just keep adding disks and they will be added as top level vdevs. Giving you maximum read and write performance due to striping data across them. Very simple, no tricks.
However if you choose FailSafe when you add your second SSD, we then do a bit of ZFS topology surgery, but only very briefly. So you start with a ZFS pool with a single top level vdev running on your current SSD. And you just added a new unused SSD and chose to transition to FailSafe mode. First we create a sparse file sized to the exact same size as your current active SSD. Then we create an entirely new pool with a single top level raidz1 vdev backed by two disks, the new SSD, and the sparse file. The sparse file acts as a placeholder for your current active SSD in the new pool. We then immediately remove the sparse file so this new pool and dataset is degraded. We then take a snapshot of the first dataset, and sync the entire snapshot over to the new pool. The system is live and running off the old pool for this whole process.
Once the snapshot has completed we then very briefly reboot to switch to the new pool. (We have the entire OS running on a writable overlay on the ZFS dataset). This is an atomic process. Early on in the boot process, before the ZFS dataset is mounted, we take an additional snapshot of the old dataset, and do an incremental sync over to the new dataset. This is very quick and copies over any small changes since the first snapshot was created.
Once this sync has completed, the two separate pools now contain identical data. We then mount the new pool and boot up with it. Then we can destroy the old pool, and attach the old SSD to the new pool, bringing it out of degraded state. And the old SSD will be resilvered in the new pool. The user is now booted up on a two wide raidz1 dataset on the new pool with bit-for-bit identical data that they shutdown on with the single ssd dataset on the old pool.
Despite sounding a bit wacky, the transition process is actually extremely safe. Apart from the switch over to the new dataset, the entire process happens in the background with the system online and fully functional. The transition can fail at almost any point and it will gracefully roll back to the single SSD. We only nuke the old single SSD at the very last step, so either we can roll back, or they have a working raidz1 array.
It sounds bad that the raidz1 goes through a period of degradation, but there is no additional risk here over not doing the transition. They are coming from a single disk vdev that already cannot survive a single disk failure. We briefly put them through a degraded raidz1 array that can also not survive a single disk loss, (no less risky than how they were already operating), to then end up at a healthy raidz1 array that can survive a single disk loss, significantly increasing the safety in a simple and frictionless way for the user.
Using two wide raidz1 arrays also get's a bit of a kneejerk reaction but it turns out for our use case the downsides are practically negligible and the upsides are huge. Mirrors basically give you 2x read speed over two disk raidz1. And less read intensive rebuilds. Everything else is pretty much the same or the differences are negligible. It turns out those benefits don't make a meaningful difference to us. A single SSD can already far exceed the bandwidth required to fully saturate our 2.5GbE connection. The additional speed of a mirror is nice but not really that noticeable. However the absolute killer feature of raidz is raidz expansion. Once we've moved to a two disk wide raidz1 array, which is not the fastest possible 2 disk configuration, but more than fast enough for what we need, we can add extra SSDs and do online expansions to a 3 disk raidz1 array and then 4 disk raidz1 array etc. As you add more disks to the raidz1 array, you also stripe reads and writes across n-1 disks, so with 4 disks you exceed the mirror perf benefits anyway.
In theory we could start with one SSD, then migrate to a mirror with the second SSD, and then again migrate to a 3 disk raidz1 array using the sparse file trick. However it's extra complexity for negligible improvements. And when moving from the mirror to the raidz1, you then degrade the user AFTER you've told them they're running FailSafe. Which changes the transition process from a practically zero additional risk operation, to an extremely high risk operation.
Ultimately what we think this design gives us is the simplest consumer RAID implementation with the highest safety guarantees that exist today. We provide ZFS level data assurance, with Synology SHR style one-by-one disk expansion, in an extremely simple and easy to use UI.
Thanks for the thorough answer. It is a little wacky and complicated but I agree it should be safe. I'm not really in the target market for your software but the hardware does look very nice. Good luck with it.
If you start with one SSD, how can you later make that into a raidz1 of two? Also, a raidz1 of two block devices does not seem like a really great idea.
"I've been told by FBI agents that they believe assassination markets are legal in the US - protected speech."
I don't believe you. Not sure what you mean by "assassination markets" exactly, but "Solicitation to commit a crime of violence" and "Conspiracy to murder" are definitely crimes.
An assassination market, at least the one we discussed, works like this - One or more people put up a bounty paid out on the death of someone. Anyone can submit a (sealed) description of the death. On death, the descriptions are opened — the one closest to the actual circumstances is paid the bounty.
One of my portfolio companies had information about contributors to these markets — I was told by my FBI contact when I got in touch that their view was the creation of the market, the funding of the market and the descriptions were all legal — they declined to follow up.
You go to therapy and try to somehow resolve this self-destructive desire constructively. That way, you might be able to avoid one of the most expensive divorces in history.
I pull into my driveway, press a button on a $15 remote, and the garage door is opened by a thing that is worth about $200. Nothing "smart" about it, and hard to see how being "smart" would improve it.
I get that some people seem to like the idea, but I have just never really understood the appeal of "smart home" stuff. I mean, "for the low, low price of several thousand dollars, we can make it so you don't have to flip light switches anymore!" is just really not an appealing offer. Flipping light switches is not a problem.
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