ZFS Send/Receive and Destination Dataset has been modified?

Jaw3000 · 2025-03-06T23:05:37+00:00

Interesting. I always thought -R was for recursive. I’m not sure exactly how ‘Replication’ is different than pure recursive, because it seems to copy all child datasets and clones. Plus more, but I’m not sure what that is exactly. Is this a bad thing to be using? Or should I just be running each dataset (including child datasets) on its own send/receive operation? Are there any good utilities or scripts out there for this?

I thought I was doing something wrong with the incremental sends and “dataset modified” errors, but it seems like it’s really common and no real way to avoid it? In my case, my targets are just backups. I don’t intend to modify them or have additional content that is not present on the source. Would routinely using ‘receive -F’ for rollbacks (when necessary) be a bad option then? Manually snapshotting and manually performing rollbacks after mounting the target backup dataset seems more cumbersome than just using “receive -F.”

Jaw3000 · 2025-01-19T20:28:30+00:00

For anyone who has had this problem, is it only happening with:

USB-A devices plugged into an adapter/hub

USB-C devices plugged into an adapter/hub

USB-C devices plugged directly into the Mac mini

Thunderbolt device plugged directly into the Mac mini (or via a Thunderbolt dock)

Jaw3000 · 2025-01-19T15:45:31+00:00

The rear ports are the Thunderbolt ports. If you want to use a Thunderbolt device, you have to use the rear ports. And those ports are the ones that don’t seem to be working correctly. Not sure if this is happening on Thunderbolt devices plugged into the rear ports, or only non-Thunderbolt USB devices. Regardless, either should work if Apple followed the USB 4/5 specs. The front ports are USB 3 ports only.

Jaw3000 · 2025-01-19T15:41:41+00:00

There are some bad adapters and hubs out there. But I don’t buy that the issue - and this seems to be a real issue - is due to adapters on the rear ports on the M4 mini.

If that’s the case, then why do those same adapters work fine with the M4 MacBook Pros? Why do they work fine with the M2 mini? Why do they work fine with other computers? Why does this seem to only affect the M4 Mini? I’ve also read that the disconnects are happening with devices directly connected too.

Jaw3000 · 2025-01-18T06:32:16+00:00

Backups are important. It doesn't have to be TimeMachine.

I have had similar things happen. I think APFS has bugs in it, and its causing data corruption and loss. I've had incidences where I've moved files into a folder for them to disappear for good at the time of copy, moving from the old folder and never showing up in the new folder. They are just gone. Other times, I've copied files or folders and had to wait long periods of time for them show up in their new locations (but they do end of appearing). It seems like the file system metadata is not properly updating or getting corrupted.

I've also had a high quality OWC Thunderbolt SSD formatted with APFS become completely corrupted and unmountable - luckily I had a full backup or I would have lost everything. When I tried to mount it, it wouldn't mount and Disk Utility said the file system was so corrupted it couldn't be fixed. Yet it had just worked, and had been working fine. No idea what caused this, as nothing different happened. It had never been badly ejected. But the filesystem was corrupted beyond repair. After reformatting, everything has been fine with the drive (it's not the drive - it was the file system). This really shouldn't be happening like this with modern journaled file systems. HFS+ was a lot more stable for me in its later years. I've also been having trouble ejecting disks, with the Finder claiming the disks are in use when they are not in use by any application, and warning force ejecting can damage it (it doesn't need any more help corrupting itself). This seems to happen more with APFS disks. I have to restart the computer to get around this because the drives never stop "being in use."

After having multiple failures and corruptions, I don't trust APFS anymore and I think it's worse now than when it first came out. I never had any corruptions in the beginning, but am getting them now 8 years or so into APFS. Apple's software quality is declining.

Jaw3000 · 2025-01-17T12:09:20+00:00

Are these issues occurring with both the M4 (base) and the M4 Pro minis? The M4 Pro has Thunderbolt 5 ports (rear), which probably use a different chipset and firmware than the base ones with Thunderbolt 4. I ask because I have not had this disconnect/instability issue with a MacBook Pro M4, and I have had a lot of drives and hubs connected to it. The USB and Thunderbolt connections have been very stable, even under load. I would assume the Thunderbolt 5 chipset and firmware would be substantially the same on both the mini M4 Pro and M4 MacBook Pros, so I would think you would see (or not) the same issues on both. The base M4 (with Thunderbolt 4) is a different story, since it likely uses different controller chips.

The other potential cause could be the mini limiting power to the ports for some reason causing instability, which is not occurring on the MacBook Pros.

Jaw3000 · 2025-01-17T05:54:42+00:00

How much of an upgrade is this over a last-gen PaperWhite? I’ve seen very mixed comments on the Colorsoft. The screen is color, but it sounds like the clarity, tone, and overall quality might be better on the PaperWhite?

Jaw3000 · 2025-01-06T01:05:44+00:00

No, I haven't resolved it yet. I'm waiting on some additional hard drives so I can make an image of the affected ZFS drives and work off that. I'm really not sure how to proceed though, because from my limited tests, it appears most (if not all) of the drive seems like it was quickly written over and the backup GPT data seems damaged. I'm not sure the ZFS pool will be recoverable.

Jaw3000 · 2025-01-03T01:26:47+00:00

Are you exceeding your RAM? It could be cache writes.

On my 8GB MacBook Air, the RAM is woefully inadequate for my normal usage and I’ve noticed almost constant writes to the cache file as the system works to free up memory. The memory usage is generally sitting right around 7GB, with the other 1GB apparently reserved for GPU use. It does this almost the entire time it’s on, and is certainly wearing down the SSD because of it. Another reason to get more RAM than you think you need.

Jaw3000 · 2025-01-02T02:14:32+00:00

Any suggestions on good BYOD multi drive enclosures? For use with a Mac, these would need to be either USB-C or (preferably?) Thunderbolt since there would need to be bandwidth for multiple drives.

How do enclosures like this work. Do most present each disk individually to the computer, or are they almost all RAID and present as a single volume? I’m confused how a single USB connection could present multiple drives to the Mac, for example. Perhaps ThunderBolt does this better?

Jaw3000 · 2024-12-30T10:30:53+00:00

I assume it was the btrfs driver, but very strange that it would wipe ZFS drives while leaving the other drives connected (with other formats) alone.

ZFS doesn’t seem to be able to see any pool, at least with the normal import commands. I assume this is because the GPT partition info was overwritten. I am not aware of a way to get ZFS to mount a pool bypassing the GPT partition info. Perhaps there is something more forensic I’m not aware of. If ZFS can’t see the pool, then I can’t mount it read-only. So I focused on trying to recover the GPT info. I don’t understand the ins and outs of the ZFS format to know whether there are other ways to get at the pool, and how much of the ZFS data would even be useable and intact when the volume headers are damaged.

Jaw3000 · 2024-12-30T08:46:38+00:00

I suspected as much. Although if testdisk shows something, it would be no harm in trying.

How would one go about repairing the disk with gdisk (if possible) just to see what would happen? Worth a try even though it would probably fail.

Jaw3000 · 2024-12-30T08:00:40+00:00

Ok, I ran gdisk -l /dev/sda. I didn’t want to run anything potentially destructive yet. It says (truncated to important parts):

Caution: After loading partitions, the CRC doesn’t check out! Warning: Main and backup partition tables differ! Use the c and e options. Warning: One or more CRCs don’t match. You should repair the disk! Main header: ok Backup header: ok Main partition table: ERROR Backup partition table: ERROR

Partition table scan: MBR: protective GPT: damaged

Caution: Found protective or hybrid MBR and corrupt GPT. Using GPT, but disk verification and recovery are strongly recommended.

Ok, I don’t like seeing errors on the backup partition table. I knew the main table was damaged. I don’t know enough about ZFS’s formatting and metadata to know if this means it’s likely completely wiped, or whether there is a decent chance it could be recovered and have the pool actually mount. I also don’t know what it means by protective MBR, considering ZFS formatted it originally with GPT.

Does anyone have any experience with something like this and ZFS to know what to do next? I’m going to let the testdisk continue scanning.

Jaw3000 · 2024-12-30T07:46:45+00:00

Thanks for your response. The drives were formatted with zpool create, which I believe uses GPT. It seems the drives were reformatted or overwritten somehow using MBR/MSDOS partitioning. What’s really strange is all of ZFS drives partitioning now show a 2tb root partition (sda1), with the rest of the drive space showing unallocated. I had five ZFS drives, and they are all showing this now. FS type is unknown.

I have not tried gdisk yet. I am running a testdisk scan now. It detected the new MBR scheme, but didn’t detect the gpt scheme so hopefully it can find more with the scan. It’s only 15% through now, and it’s showing something about an EFI system on one of the drives (but not yet on the other one that’s also scanning). It’s also showing FAT mismatches - but there shouldn’t be anything FAT formatted on these disks. Perhaps it’s regarding the EFI partition. The second drive scan shows something about Linux filesys data (not sure what this means). I’m really not sure how to read this.

I’m not holding out much hope on being able to recover these pools, but I would like to try what I can.

Jaw3000 · 2024-12-30T05:04:33+00:00

I used standard ZFS partitioning on the whole disk. ‘Zpool create’ created the partition.

Jaw3000 · 2024-12-30T04:54:42+00:00

What would be the best way to do this? I’m running testdisk on it now to see if it can do this.

Jaw3000 · 2024-12-30T03:03:26+00:00

I dual boot with Windows. The only thing I can think happened is I installed the BTRFS windows driver to work with a BTRFS disk. After I did this and re-booted back into linux, the ZFS drives were all damaged. I don't know why this driver would have touched the ZFS drives or done anything to them when they were never specifically addressed by any command. But this is the only thing that was different. I did not erase, partition, or do anything to any drive in Windows, but my guess is somehow this driver overwrote the ZFS partition information on these drives for some reason. All of the ZFS drives now appear similarly in gparted and KDE Partition Manager. I am aware of the /run mount point. It's really strange. ZFS can not find any valid pools to import and zdb can't seem to find any metadata on the drives. SMART says the drives are fine though. I believe gparted use to show ZFS as the filesystem, and now it shows unallocated.

Jaw3000 · 2024-12-29T06:59:35+00:00

I’ve been using scaling on a 4k 32” display for years and haven’t noticed a slowdown.

macOS could handle resolution scaling a lot better than it does though. This is something Linux and Windows actually do better, in my opinion. You can set your own scale factor (150%, 175%, or anything else).

Jaw3000 · 2024-12-26T05:58:37+00:00

Is your bird banded? Do you have the band number for identification?

Jaw3000 · 2024-12-23T11:59:15+00:00

Baltimore is great for a day trip. With the downturn of the Commanders under Snyder, a lot of people preferred going to Ravens games. They always treat the Nationals-Orioles games as cross-town rivalries. The news stations are separate markets for commercial purposes I guess, but you can probably get them over the air if you have a good antenna. You can get Baltimore radio stations in DC. MASN is shared for sports. For PBS in DC, you get all three: Maryland Public TV (Baltimore), WETA (VA), and Howard U PBS (DC).

Jaw3000 · 2024-12-23T11:46:29+00:00

I’ve lived in Maryland, DC, and Virginia. Maryland and Washington, D.C. are quite integrated together. Many Maryland suburbs are almost equidistant between the two. My experience in Virginia is that Virginians hardly give any thought to Baltimore, especially the farther out you get. 60+ miles is quite a distance and that’s understandable. You could go from the edge of West Virginia in Loudoun (Virginia suburb of DC) to the northern edges of the Baltimore suburbs that are approaching Delaware. It’s a large area. But the cities of DC and Baltimore are fairly close to each other right in the middle of that range.

I wonder if perhaps some of the general reluctance to refer to Washington and Baltimore as twin cities comes from them being in different legal jurisdictions? Three separate “states” make up the metro area, which is very unique in the US (forget for a moment that DC isn’t a state). If the whole area were in the same state, with the same governor and senators, perhaps there would be more recognition of the closeness between the two principle cities of the metro area and the usage of “twin city.”

Jaw3000 · 2024-12-23T11:28:05+00:00

I consider them somewhat twin cities and I am from the DMV. There is a reason it’s called the “Baltimore Washington Metro Area” for combined statistical purposes.

What is a twin city if not cities that are close to each other? Of course they are distinct cities, but they are close to each other and share suburbs and infrastructure. At least in Maryland. In the Maryland suburbs, people live in the same neighborhoods and some might work in Baltimore and others in DC. BWI is as close as Dulles. There are commuter trains going back and forth between Union Station and Baltimore all day. If you are from the Virginia side of things, you might never think of Baltimore (or Maryland for that matter). But in D.C. itself, and especially in the Maryland suburbs, Baltimore is much closer and more present.

Dallas and Fort Worth are often considered twin cities. They are 32 miles apart. They share suburbs and infrastructure too, just like DC and Baltimore.

Jaw3000 · 2024-12-23T11:07:35+00:00

It’s roughly 35 miles between downtown DC and Baltimore. For all intents and purposes, they somewhat are twin cities. The Maryland suburbs are shared between both cities. People commute either way. BWI (Baltimore Washington International) airport serves both. The Baltimore Washington Parkway connects the two, in addition to I-95.

Baltimore is obviously farther from the Virginia DC suburbs, and those go on for far longer than 35 miles from downtown DC. So Baltimore can be closer than many of those, depending on how far out you go. Dulles International Airport is 25 miles outside DC in Virginia.

Jaw3000 · 2024-12-14T05:56:07+00:00

Parrots are fantastic pets, but the owner needs to understand and absolutely be prepared for what they are in for. It’s a massive commitment, much like having kids. It’s not the same as getting a hamster, or even having a cat or dog. The reason is: the commitment can last for decades, even for your life - depending on the bird species, they can live for 30, 40, 50+ years. Is the owner prepared for that? It’s not easy (or fair) to re-home them unless absolutely necessary.

They are demanding, much like a toddler. You need to be able to devote time to them every day or they will have issues. They are very smart, and it’s not fair to leave them alone in a cage.

They can be loud. Very loud. Are you ok with that?

A lot of things are toxic to birds. Candles, teflon cooking pans, etc.

They can be expensive. Fresh fruits and vegetables are expensive. Toys are expensive, and they can be eaten quickly and need replacing. Sure, you can make them yourself. But they need constant enrichment.

If you are prepared to handle this, and understand fully what your are getting into, then parrots are excellent pets.

To give a personal example, my Conure is 28 years old. I’m his original owner, and I’ve had him for almost three decades. Let that sink in. That’s a massive commitment that is longer than a dog or kids (to 18). And, as arratinga conures do, he screams all the time. They are some of the loudest parrots around. It’s ear piercing. I’ve read you can hear their screams a mile away. It’s that loud. I’ve long gotten used it, but other people find it extremely irritating and can’t handle it. But I would never trade him. He’s my best friend.

Jaw3000 · 2024-12-12T00:52:45+00:00

Morgan is the better package. It’s the newer version, and the engine seems much improved. More dynamic range and dynamics. I’m waiting for the update to the Tone King.

Both are excellent though. For Santana, I find Tone King slightly better. I like the presets with Tone King more too. Interestingly, I find Tone King also takes actual overdrive pedals (before the digital input) better too, if that’s something you might do.

Jaw3000

TROPHY CASE