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Comment Re:BTRFS is getting there (Score 1) 279

The problem with zfs clone is that "clones can only be created from a snapshot" which means that deleting a file from a clone does not delete the file from the underlying snapshot, so the space is never actually freed

zfs promote clone-filesystem && zfs destroy clone-filesystem@snapshot-it-was-based-on

Comment Re:BTRFS is getting there (Score 2) 279

This is one of the things the Solaris-derived versions have tended to be better at handling - ZFS expects failing drives to be detected/managed by an external fault management service (fmd) which doesn't exist on other OS's. ZFS itself doesn't mark a drive as bad itself unless it outright disappears from the system.

Comment Re:BTRFS is getting there (Score 1) 279

- Mutable snapshots. It is infuriating that ZFS's snapshots are immutable.

Er, snapshots should be immutable. They're used as sources for backups and replication, allowing them to be mutable would defeat the main purpose.

zfs clone if you want a writable copy. What's wrong with that?

ZFS is designed for extremely high quality hardware (and lots of RAM) that doesn't lie to the OS

ZFS is designed to be robust in face of crappy lying disks. That's what all the checksumming and self healing is about - ZFS will cope *far* better with your dire consumer drives than most traditional filesystems. But yes, it likes its RAM, and it likes its redundancy.

Comment Re:BTRFS is getting there (Score 1) 279

That's only a very partial solution - vdev removal, not vdev shrinking. And it's got a pretty meh way of going about it (removing a vdev leaves a permanent layer of redirection in its place).

What we want is something called "block pointer rewriting", which would allow far more flexibility in the modification of an existing pool - possibly even dynamically changing RAID levels on the fly. Unfortunately it's a massive job that nobody's sufficiently interested in solving.

Comment Re:... using the name and e-mail address of other (Score 1) 319

My gmail address gets used as a throwaway rather a lot, and you'd be surprised at the number of sites that don't bother at all.

This message was sent to you ($foo@gmail.com) because you are a valued NBA fan registered with us and we wanted to wish you a happy birthday!

Hi meleonaz,

Registered email successfully updated
Your email address for the account meleonaz has been successfully updated to $foo@gmail.com

Hi @notme345,
We got a request to reset your Instagram password.

Thanks so much for joining Pandora! We're very happy to have you on board, and we look forward to providing you with endless hours of great music listening and discovery.

Many more sites will still create the account and let you use it without me validating the email, and many more provide no means of saying this *isn't* their email.

Comment Re:Your link explains the problem (Score 2) 111

Because a lot of security boils down to "I'm thinking of a number between 0 and $something, I bet an attacker can't guess it at a rate better than blind chance".

e.g. a 128 bit encryption key is a number between 0 and 340282366920938463463374607431768211455. With a secure random number generator, an attacker will have to on average test half of those possible keys before he finds the correct one, because he can't know anything that will reduce the space he has to search.

If your random number generator is broken - for an extreme example, say you only seed it with a 16-bit process ID - suddenly the random values you generate are trivially guessable, because there's only 65535 possible streams of randomness to check instead of $impossibly_huge_number. What should have taken longer than the age of the universe to crack now takes mere seconds.

Comment Er, what? (Score 1) 371

Users who upgrade to 10 will have their default browser automatically changed to the new Edge browse

I upgraded and it gave me a clear screen showing the new defaults, and an option to keep my existing ones, which I chose.

After booting, MPC-HC was still my default video player, foobar2000 was still my default music player, and Opera was still my default browser.

Submission + - HardenedBSD Completes Strong ASLR Implementation (hardenedbsd.org)

HardenedBSD writes: A relatively new fork of FreeBSD, HardenedBSD, completed their Address Space Layout Randomization (ASLR) feature. Without ASLR, applications are loaded into memory in a deterministic manner. An attacker who knows where a vulnerability lies in memory can reliably exploit that vulnerability to manipulate the application to doing the attacker's bidding. ASLR removes the determinism, making it so that an attacker knows that a vulnerability exists, but doesn't know where that vulnerability lies in memory. HardenedBSD's particular implementation of ASLR is the strongest form ever implemented in any of the BSDs.

With HardenedBSD having completed their ASLR implementation, the next step is to update documentation and submit update the patches they have already submitted upstream to FreeBSD. ASLR is the first step in a long list of exploit mitigation technologies HardenedBSD plans to implement. HardenedBSD has also implemented other exploit mitigation, security, and general hardening features, providing great security for FreeBSD.

Comment Re:File versioning and backup flags (Score 1) 484

DragonFlyBSD's HAMMERFS does much of this - you can examine the version history of files and directories using hammer history and undo commands, and reference versions directly by appending @@ to filenames.

You can control how long history is preserved for and in what level of detail, as well as efficiently replicate it all across the network to remote filesystems (which can have their own, different rules). All this in addition to the more traditional named snapshots approach you're limited to with, e.g. ZFS.


Comment "Best"? (Score 1) 558

Guess that has to be my main server, even though it's a few generations older than my desktop, it has more cores, more IO, more memory and more storage. It runs FreeBSD.

Case: SuperChassis 745TQ-R800B (pic)

Motherboard: Supermicro X8DTN+

CPUs: 2 x 6-core Xeon L5639 @ 2.13GHz

RAM: 144GB - 9 x 16GB DDR3-1333 ECC Reg

Primary Storage: 2 x SanDisk Extreme Pro 960GB, ZFS mirror.

Mass Storage: 6 x 5TB Toshiba MD04ACA5, ZFS 3 x mirror.

Disk controller: IBM M1015, seems one of the most favoured HBA's these days.

Keyboard: NTC KB-6153EA with clicky White Alps.

I play with search engines and stuff, the memory comes in handy and I got it for a great price.

Desktop is a 32GB ECC quad core Haswell Xeon mumble mumble running Windows 8.1, with a pair of 30" 1600p monitors and a 20" 1600x1200. Nice having space to put stuff. Also nice having memory that doesn't silently corrupt itself every few months, you crazy kids and your non-parity.

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