What are the alternatives to btrfs? At 12 TB data checksums are a must unless the data tolerate bit-rot. And if one wants to stick with the official kernel without out-of-tree modules, btrfs is the only choice.
I tried btrfs on three different occasions. Three times it managed to corrupt itself. I'll admit I was too enthousiastic the first time, trying it less than a year after it appeared in major distros. But the latter two are unforgiveable (I had to reinstall my mom's laptop).
I've been using ZFS for my NAS-like thing since then. It's been rock solid ().
(): I know about the block cloning bug, and the encryption bug. Luckily I avoided those (I don't tend to enable new features like block cloning, and I didn't have an encrypted dataset at the time). Still, all in all it's been really good in comparison to btrfs.
Good thing all disks these days have data checksums, then!
(50TB+ on ext4 and xfs, and no, no bit rot. Yes, I've checked most of it against separate sha256sum files now and then. As long as you have ECC RAM, disks just magically corrupting your data is largely a myth.)
Less mythic on SSDs than spinning rust, in my experience.
Not particularly frequent either way, but I have absolutely had models of SSDs where it became clear after a few months of use that a significant fraction of them appeared to be corrupting their internal state and serving incorrect data back to the host, leading to errors and panics.
(_usually_ this was accompanied by read or write errors. But _usually_ is notable when you've spent some time trying to figure out if the times it didn't were a different problem or the same problem but silent.)
There was also the notorious case with certain Samsung spinning rust and dropping data in their write cache if you issued SMART requests...
Isn't bcachefs even younger and less polished than btrfs? It does show more promise as btrfs seems to have fundamental design issues... but still I wouldn't use that for my important data.
I don't disagree. Gotta backups for important data either way too!
Just talking about filesystems with checksumming (and multidevice). Any new filesystem to support these features is going to be newer.
I've had both btrfs and bcachefs multidevice filesystems lock up read-only on me. So no real data loss, just a pain to get the data into a new file system, the time it was an 8 drive array on btrfs.
Could try ZFS or CephFS... even if several host roles are in VM containers (45Drives has a product setup that way.)
The btrfs solution has a mixed history, and had a lot of the same issues DRBD could get. They are great until some hardware/kernel-mod eventually goes sideways, and then the auto-heal cluster filesystems start to make a lot more sense. Note, with cluster based complete-file copy/repair object features the damage is localized to single files at worst, and folks don't have to wait 3 days to bring up the cluster on a crash.
lvm only supports checksums for metadata. It does not checksum the data itself. For checksums with arbitrary filesystems one can have dm-integrity device rather than LVM. But the performance suffer due to separated journal writes by the device.
Physical SIM cards are just as secure as the security enclave on the phone. In Norway few years ago banks even used that for secure authentication that worked on dumb phones with local mobile network providers pre-installing the required software on their SIM cards.
But then to save cost including the support cost banks stopped and instead started to require a non-rooted Android/iPhone.
Or optimize the os because I still find 8GB insane for everyday tasks. Ok, gaming I can understand, but most common tasks should be runnable with at most 2GB of memory and that is mostly for browsers.
Nuclear is not that steady. Nuclear plants require a lot of water to cool things. And when a particular hot summer happens, rivers dry out and nuclear reactors have to scale down the power production or even be shutdown. And then they require quite significant maintenance periodically.
Granted, in Europe a hot dry summer is when solar is at its peak. So it is much lesser problem than a cold winter with a lot of cloudy days with no wind when nuclear energy is ideal.
Still from a perspective of 20 years ago with unknown prospects about renewables natural gas power stations were considered much more reliable and flexible power source compared with nuclear and way more cleaner than coal. Of cause, as long as one gets gas.
APKWS interceptor is about 35K USD and works much better than drone-based interceptors. The problem is to scale the production, training and deployment. Another problem is detection. One needs wast multilayered system that US military missed to build as big stationary radars are very hard to defend.
Air-launched interceptors like this have the problem on relying on a super-expensive manned carrier (fighter or helicopter).
The intercept cost is now not only the cost of the interceptor, but also the cost of the flying hours of the launching platform, and the risk of losing the launching platform.
If you equip even some of your Shaheds with AA missiles (cheap manpads with autonomous IR target acquisition and guidance), like is already happening in Ukraine, the feasibility of APKWS becomes problematic. The technology is developing fast these days.
APKWS launching from air is a stop-gap measure in any case. The detection range for Shahed-type drones is tenths of kilometers, not hundreds, like with fighter jets or big missiles. One cannot have that many fighter jets in the air all the time even without the threat of manpads.
But ground-based platforms work just fine and cheap enough to scale up the deployment to cover the big area.
The big advantage of APKWS over interceptor drones is the rocket engine, they are much faster and can catch Shaheds within much bigger radius or within much smaller timeframe than interceptor drones.
First, if I understand correctly, APKWS is laser guided (one of the reasons it is relatively cheap is cheap simple guidance), it needs the carrier to designate the target.
Second, it is rather short range, and that range is helped significantly by the speed and altitude of the launching platform. Launching from the ground upwards would significantly reduce its range, which is anyway just a few km.
Due to the short range, you will need a densely distributed significant numbers of them, and still be in danger of saturation attack (the attacker can saturate one route, you have to be ready for all possible routes). Having a carrier platform allows the missiles to be quickly brought where they are needed, so overall you need much less of them (still too much, as having enough carriers in air imposes limits as well).
You can have longer-range ground missiles, but then the costs rise. Also, I am not sure how feasible/robust is to laser designate air targets from the ground. I suspect it does not work over longer distances, i.e. you need a more sophisticated and costly guidance system/sensor suite on the missile.
The beauty of an anti-drone drone is that you have a much more robust human-assisted guidance, for cheap (camera and communication link). With advances to AI, even that human and communication link are becoming obsolete...
With rocket propelled missile you have much faster closing speed, and quite limited energy budget - essentially you have to make a correct decision fast and precisely, otherwise the missile is wasted. With a drone, everything is slower and easier to correct.
The latest APKWS is IR guided and works in fire and forget mode that works nicely from the ground. And then drone interceptor struggles with Russians Shaheds with jet engines.
On the other hand the latest development with drone interceptors is rocket booster to quickly bring in within Shahed. So I guess there would be a convergence between APKWS and interceptor drones.
IR guided fire and forget is fine, but undoubtedly quite a bit costlier than the basic laser-guided one. If you want to use it against jet engined Shaheds while launching from the ground, you definitely need larger rocket motor, i.e. costlier interceptors. But that might be fine, the jet engined Shaheds are not as cheap as the basic ones anyway.
Actually, I am surprised they still use the Shahed platform for the jet engined drones. A Reaper-like platform with high aspect ratio wings would be much more aerodynamically efficient, allowing longer range/loiter time/larger payload. It is definitely more expensive airframe, but that jet engine might be the main cost factor anyway.
Re: IR seeker against plain Shaheds: does the basic weedwhacker Shahed have enough IR signature? (More precisely: does it have it if you did some basic precautions - cover the engine, some mixing of the ambient air with the exhaust.) The power level of that engine (= the whole source of IR energy) is quite low...
Shahed shape is dictated by the need to sustain very high G and aerodynamic forces during the launch from a truck which in turn allows for a very fast deployment. Anything more aerodynamic will imply stronger, more expensive frame and less payload.
Shahed has sufficiently bright IR that even a basic seeker works. To keep the cost low no efforts were applied to minimize the signature.
It is fascinating how well designed Shahed was for its intended purpose of being the cheapest mass-produced platform that would saturate any advanced air defenses while hard to track launch site. However, with appearance of cheap mass-produced counter-measures it may no longer be optimal.
With Bayraktar it was a software update for radar that allowed for Russian to destroy them. The radar signature of Bayraktar was way off from a typical target that radars were looking for at the beginning of the war.
It is vastly more complicated to find targets at 1500 miles than at 20. So drones are effective at destroying big stationary civilian infrastructure and much less at long distance strikes at military targets. Russia's inability to destroy Ukrainian aviation is a good example.
But then with solar and batteries civilian infrastructure becomes much more resilient against drone strikes.
At a certain distance, I'd contend all infrastructure is big and static. Our energy comes from large facilities, without these facilities continent scale infrastructure will grind to a halt at 1500 miles. Rail, power lines, warehouses, factories and trucks are all relatively static. It's not unreasonable to expend a Shahed type drone on a simple semi-truck parked overnight from nearly a continent away. There are only 3 million semi-trucks in the entire US, and I'd be shocked if the country could run without them.
Ukraine tried to come up with drones that can fly over 1000 miles. But drones the size of Shaheds just cannot fly that distance without significantly reducing the warhead. To attack things beyond that range Ukraine have used essentially Cessna. Which is much more expensive and visible on radars.
Instead Ukraine came up with an idea of mass producing extremely simple cruise missiles that could fly 2000 miles and deliver up to a ton of explosives with a cost of 100K and make 1000 of them per month. But then it seems Russia was able to discover the production sites and destroy them.
> It is vastly more complicated to find targets at 1500 miles than at 20.
It's true but they are so cheap that launching a whole bunch and/or improving them incrementally is possible. Yeah they are for stationary targets mostly, for sure. And of course their sounds and relatively low speed does make them somewhat easier to shoot down with short range AA guns and can have automated acoustic early warning system (it's like a flying lawnmower or chainsaw).
Average age of cars in Norway is higher than in many other countries due to high taxes on cars.
And then in China number of cars per capita is much less then in West. As more and more people there can afford a car and that car will be EV, transitioning to mostly EV should happen faster than in Norway.
Russia has been recovering from Ukrainian drone strikes again oil industries within months. And Ukraine inflicted much serious damage than Iran on Gulf states.
Drones with 100-150kg just not capable of inflicting hard to recover damage. What they are good is striking repeatedly. But judging by numbers Iran is not capable any longer of sustained stacks with hundreds of drones per day.
Very interesting take. Not sure about the comparisons though: 1) Russia is a huge powerhouse that can do a lot on its own, I don't think Gulf states have the same capability to recover (at least that's what energy analysts are saying), 2) The US claimed they had completely maimed Iran in the first few days of the war, saying they had fully destroyed their navy and their missile launching capabilities. However, that clearly doesn't seem to be the case, and yesterday Iran even downed an F35, which until then was thought of as an almost impossible feat
I guess there's a lot up in the air right now, so I personally wouldn't bet on things getting better that quickly
The same analysts predicted that it would take years for Russia to recover from the strikes. And Russia is no longer a powerhouse. They gets most of their equipment from China including the oil and gas industries.
As for Iran just count the number of drones it uses per day. They started from hundreds but now it is below 50.
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