Plus our favorite features from Fedora 32, and why Wes loves DNF.

Links:

• What's new in Fedora 32 Workstation
• Fedora 32 ChangeSet
• Linux distro review: Fedora Workstation 32
• TechSNAP 428: RAID Reality Check
• ZFS versus RAID: Eight Ironwolf disks, two filesystems, one winner
• Understanding RAID: How performance scales from one disk to eight
• Find Jim on 2.5 Admins
• Find Wes on LINUX Unplugged
• TechSNAP 1: First episode of TechSNAP (in 2011!)
• TechSNAP 300: End of the Allan and Chris era (2017)
• TechSNAP 301: Enter Dan and Wes
• TechSNAP 347: A Farewell to Dan
• TechSNAP 348: Chris is back!
• TechSNAP 389: Jim's first time as a guest
• TechSNAP 390: Jim's second guest appearance
• TechSNAP 393: Chris says goodbye
• TechSNAP 395: Jim joins the show

Plus Intel's surprisingly overclockable laptop CPU, why you shouldn't freak out about 5G, and the incredible creativity of the Demoscene.

Links:

• Asus ROG Zephyrus G14—Ryzen 7nm mobile is here, and it’s awesome
• Linux on Laptops: ASUS Zephyrus G14 with Ryzen 9 4900HS
• Intel’s 10th-generation H-series laptop CPUs break 5GHz | Ars Technica
• Wi-Fi 6E becomes official—the FCC will vote on rules this month
• Celebs share rumors linking 5G to coronavirus, nutjobs burn cell towers
• Not-actually Linux distro review: FreeBSD 12.1-RELEASE
• Not actually Linux distro review deux: GhostBSD
• MOD (file format) - Wikipedia
• AT&T.MOD (YouTube)
• DJ Moses Rising—Ice Cream Trance (YouTube)
• Farbrausch—The Product (64K Intro, 2000)
• Farbrausch—Poem to a Horse (64K Intro, 2002)
• Finland accepts the Demoscene on its national UNESCO list of intangible cultural heritage of humanity

Plus we celebrate WireGuard's inclusion in the Linux 5.6 kernel, and fight some exFAT FUD.

Links:

• WireGuard VPN makes it to 1.0.0—and into the next Linux kernel — It's a good day for WireGuard users—DKMS builds will soon be behind us.
• Linux 5.6 Is The Most Exciting Kernel In Years With So Many New Features
• fs: New zonefs file system — zonefs is a very simple file system exposing each zone of a zoned block device as a file. This is intended to simplify implementation of application zoned block device raw access support by allowing switching to the well known POSIX file API rather than relying on direct block device file ioctls and read/write.
• Ama-ZNS! Zonefs File-System Will Land with Linux® 5.6
• What is Zoned Storage and the Zoned Storage Initiative? — Zoned Storage is a new paradigm in storage motivated by the incredible explosion of data. Our data-driven society is increasingly dependent on data for every-day life and extreme scale data management is becoming a necessity.
• Linux Kernel Support - ZonedStorage.io
• dm-zoned — The dm-zoned device mapper target exposes a zoned block device as a regular block device.
• Device Mapper - ZonedStorage.io
• What are PMR and SMR hard disk drives?
• Beware of SMR drives in PMR clothing — WD and Seagate are both submarining Drive-managed SMR (DM-SMR) drives into channels, disguised as "normal" drives.
• Beware of SMR drives in PMR clothing [Reddit]
• The exFAT filesystem is coming to Linux—Paragon software’s not happy about it — When software and operating system giant Microsoft announced its support for inclusion of the exFAT filesystem directly into the Linux kernel back in August, it didn't get a ton of press coverage. But filesystem vendor Paragon Software clearly noticed this month's merge of the Microsoft-approved, largely Samsung-authored version of exFAT into the VFS for-next repository, which will in turn merge into Linux 5.7—and Paragon doesn't seem happy about it.
• The New Microsoft exFAT File-System Driver Is Set To Land With Linux 5.7
• Speeding up Linux disk encryption - The Cloudflare Blog — Encrypting data at rest is vital for Cloudflare with more than 200 data centres across the world. In this post, we will investigate the performance of disk encryption on Linux and explain how we made it at least two times faster for ourselves and our customers.
• Add inline dm-crypt patch and xtsproxy Crypto API patch

Plus Let's Encrypt's certificate validation mix-up, Intel's questionable new power supply design, and more.

Links:

• Let's Encrypt changes course on certificate revocation
• Revoking certain certificates on March 4
• Let's Encrypt: Incomplete revocation for CAA rechecking bug
• Pass authzModel by value, not reference
• The Complete Guide to CAA Records
• DNS Certification Authority Authorization
• AMD's 7nm Ryzen 4000 laptop processors are finally here
• How Intel is changing the future of power supplies with its ATX12VO spec
• Single Rail Power Supply ATX12VO Design Guide
• FreeNAS and TrueNAS are Unifying
• FreeNAS and TrueNAS are Unifying [Video Announcement]
• Ubuntu 20.04's zsys adds ZFS snapshots to package management
• ubuntu/zsys: zsys daemon and client for zfs systems

Plus Jim's journeys with Clear Linux, and why Ubuntu 18.04.4 is a maintenance release worth talking about.

Links:

• Ubuntu 18.04.4 LTS: here's what's new — It's not as shiny and exciting as entirely new versions, of course, but it does pack in some worthwhile security and bugfix upgrades, as well as support for more and newer hardware.
• 18.04.4 - Ubuntu Wiki
• MobaXterm — Enhanced terminal for Windows with X11 server, tabbed SSH client, network tools and much more.
• Linux distro review: Intel’s own Clear Linux OS — There's not much question that Clear Linux is your best bet if you want to turn in the best possible benchmark numbers. The question not addressed here is, what's it like to run Clear Linux as a daily driver? We were curious, so we took it for a spin.
• Clear Linux* Project — Clear Linux OS is an open source, rolling release Linux distribution optimized for performance and security, from the Cloud to the Edge, designed for customization, and manageability.
• swupd — Documentation for Clear Linux* project
• clr-boot-manager: Kernel & Boot Loader Management
• Cannot compile zfs for 5.5-rc2 · Issue #9745 · zfsonlinux/zfs
• Persistent L2ARC might be coming to ZFS on Linux — The primary ARC is kept in system RAM, but an L2ARC device can be created from one or more fast disks. In a ZFS pool with one or more L2ARC devices, when blocks are evicted from the primary ARC in RAM, they are moved down to L2ARC rather than being thrown away entirely. In the past, this feature has been of limited value, both because indexing a large L2ARC occupies system RAM which could have been better used for primary ARC and because L2ARC was not persistent across reboots.
• Persistent L2ARC by gamanakis · Pull Request #9582 · zfsonlinux/zfs — This feature implements a light-weight persistent L2ARC metadata structure that allows L2ARC contents to be recovered after a reboot. This significantly eases the impact a reboot has on read performance on systems with large caches.
• LINUX Unplugged 303: Stateless and Dateless — We visit Intel to figure out what Clear Linux is all about and explain a few tricks that make it unique.
• LINUX Unplugged Blog: Clear Linux OS 2019
• HAMR don’t hurt ’em: laser-assisted hard drives are coming in 2020 — Although the 2012 "just around the corner" HAMR drives seem to have been mostly vapor, the technology is a reality now. Seagate has been trialing 16TB HAMR drives with select customers for more than a year and claims that the trials have proved that its HAMR drives are "plug and play replacements" for traditional CMR drives, requiring no special care and having no particular poor use cases compared to the drives we're all used to.
• HAMR Milestone: Seagate Achieves 16TB Capacity on Internal HAMR Test Units
• Western Digital debuts 18TB and 20TB near-MAMR disk drives
• Previously on TechSNAP 341: HAMR Time — We've got bad news for Wifi-lovers as the KRACK hack takes the world by storm; We have the details & some places to watch to make sure you stay patched. Plus, some distressing revelations about third party access to your personal information through some US mobile carriers. Then we cover the ongoing debate over HAMR, MAMR, and the future of hard drive technology & take a mini deep dive into the world of elliptic curve cryptography.

Plus Debian's continued init system debate, and our frustrations over 5G reporting.

Links:

• 5G Underwhelms in Its First Big Test - WSJ
• How South Korea built 5G, and what it's learning - RCR Wireless News
• After seven months, here’s what South Korea can teach us about 5G - CNA
• South Korea secures 4 million 5G subscribers | ZDNet
• Debian Developers Take To Voting Over Init System Diversity
• Debian GR Results
• General Resolution: Init systems and systemd
• Ringing In 2020 By Clang’ing The Linux 5.5 Kernel - Benchmarks Of GCC vs. Clang Built Kernels
• Using LLVM Clang To Compile The Linux Kernel Is Heating Up Again Thanks To Google
• Building the kernel with Clang - LWN
• ClangBuiltLinux
• Compiling the Linux kernel with LLVM tools (FOSDEM 2019)

Plus why you may want to skip Nest Wifi, and our latest explorations of long range wireless protocols.

Links:

• Decoding LoRa: Realizing a Modern LPWAN with SDR — LoRa is an emerging Low Power Wide Area Network (LPWAN), a type of wireless communication technology suitable for connecting low power embedded devices over long ranges. This paper details the modulation and encoding elements that comprise the LoRa PHY, the structure of which is the result of the author’s recent blind analysis of the protocol. It also introduces grlora, an open source software defined implementation of the PHY that will empower wireless developers and security researchers to investigate this nascent protocol.
• Nest Wifi announced at Made by Google 2019 | Ars Technica — Google says that a two-piece Nest Wifi kit—one Nest Router and one Nest Point—should cover up to 3,800 square feet and 85% of homes. This claim, like most arbitrary claims of Wi-Fi coverage with no real detail, should be taken with several grains of salt.
• TP-LINK EAP series Business Wi-Fi Solution — The EAP Series Business Wi-Fi Solution incorporates EAP Series hardware, which provides a smooth, reliable wireless internet experience, and a powerful centralized management platform.
• Bloody Stupid Johnson | Discworld Wiki — Although evidently able in certain fields, Johnson is notorious for his complete inability to produce anything according to specification or common sense, or (sometimes) even the laws of physics.
• A Quick Look At EXT4 vs. ZFS Performance On Ubuntu 19.10 With An NVMe SSD — For those thinking of playing with Ubuntu 19.10's new experimental ZFS desktop install option in opting for using ZFS On Linux in place of EXT4 as the root file-system, here are some quick benchmarks looking at the out-of-the-box performance of ZFS/ZoL vs. EXT4 on Ubuntu 19.10 using a common NVMe solid-state drive.
• ubuntu/zsys: zsys daemon and client for zfs systems — It allows running multiple ZFS systems in parallel on the same machine, get automated snapshots, managing complex zfs dataset layouts separating user data from system and persistent data, and more.
• Ubuntu ZFS support in 19.10: ZFS on root · ~DidRocks — We are shipping ZFS On Linux version 0.8.1, with features like native encryption, trimming support, checkpoints, raw encrypted zfs transmissions, project accounting and quota and a lot of performance enhancements.
• Ubuntu ZFS support in 19.10: introduction · ~DidRocks — We want to support ZFS on root as an experimental installer option, initially for desktop, but keeping the layout extensible for server later on.
• A detailed look at Ubuntu’s new experimental ZFS installer | Ars Technica — If you're new to the ZFS hype train, you might wonder why a new filesystem option in an OS installer is a big deal. So here's a quick explanation: ZFS is a copy-on-write filesystem, which can take atomic snapshots of entire filesystems.

Plus when not to use ZFS, the surprising way your disks are lying to you, and more!

Links:

• ZFS - Ubuntu Wiki — ZFS is a combined file system and logical volume manager designed and implemented by a team at Sun Microsystems led by Jeff Bonwick and Matthew Ahrens.
• Performance tuning - OpenZFS — Make sure that you create your pools such that the vdevs have the correct alignment shift for your storage device's size. if dealing with flash media, this is going to be either 12 (4K sectors) or 13 (8K sectors).

Plus a concise breakdown of Meltdown, Spectre, and side-channel attacks like only TechSNAP can.

Then we run through the timeline of events, and the scuttlebutt of so called coordinated disclosure. We also discuss yet another security issue in macOS High Sierra, a backdoor in popular storage appliances, your questions, and more!

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Links:

• Meltdown and Spectre — Meltdown and Spectre exploit critical vulnerabilities in modern processors.
• The Meltdown and Spectre CPU Bugs, Explained
• How we got to Spectre and Meltdown A Timeline My version of the timeline... — My version of the timeline on Spectre Meltdown. This post will be updated! If you want to add/correct something, please comment.
• How Tier 2 cloud vendors banded together to cope with Spectre and Meltdown | TechCrunch — Eventually six cloud providers — Scaleway, DigitalOcean, Packet, Vultr, Linode and OVH — formed a consortium of sorts to help one another and share information. In order to make the process more efficient, they started a Slack channel with CEOs, CTOs and engineers from the various companies sharing information and fixes as they became available.
• FreeBSD was made aware of Meltdown and Spectre in late December. There's currently no ETA for mitigation. — It looks like Dragonfly BSD has a patch, so hopefully that will be useful for FreeBSD.
• heads up: Fix for intel hardware bug will lead to performance regressions — Upcoming versions of the linux kernel (and apparently also windows and others), will include new feature that apparently has been implemented with haste to work around an intel hardware bug.
• AWS Developer Forums: Degraded performance — Immediately following the reboot my server running on this instance started to suffer from cpu stress.
• Google is pushing Retpoline — With Retpoline, we could protect our infrastructure at compile-time, with no source-code modifications. Furthermore, testing this feature, particularly when combined with optimizations such as software branch prediction hints, demonstrated that this protection came with almost no performance loss.
• PCID is now a critical performance/security feature on x86 — On any system that does not currently show "pcid" in the flags line of /proc/cpuinfo, Meltdown is a bigger issue than "install latest updates".
• Spectre & Meltdown vulnerability/mitigation checker for Linux — A simple shell script to tell if your Linux installation is vulnerable against the 3 "speculative execution" CVEs that were made public early 2018.
• Microsoft PowerShell Script to check for Meltdown — To help customers verify that protections are enabled, Microsoft has published a PowerShell script that customers can run on their systems. Install and run the script by running the following commands.
• Why Raspberry Pi isn't vulnerable to Spectre or Meltdown — To help us understand why, here’s a little primer on some concepts in modern processor design.
• macOS High Sierra's App Store System Preferences Can Be Unlocked With Any Password — A bug report submitted on Open Radar this week has revealed a security flaw in the current version of macOS High Sierra that allows the App Store menu in System Preferences to be unlocked with any password.
• Major macOS High Sierra Bug Allows Full Admin Access Without Password
• WD My Cloud NAS devices have hard-wired backdoor — Lets anyone log in as user mydlinkBRionyg with the password abc12345cba.
• Question: How could I measure all of these overhead performance hits? — My question: how could I measure all of these overhead performance hits, so I can put in a well educated request to adjust all of these components, so I have a computer that performs near its capacity?
• Perfmon
• Troubleshooting with the Windows Sysinternals Tools
• ProcDump
• Process Monitor - Replaces filemon
• Question: MySQL Replication Woes — The problem is that during some larger deletes on the master, the tables on the slave get locked and the slave lag goes through the roof.. During this time all of my selects that have been sent to the slave are just sitting there and waiting for the table to unlock while the master is just fine.
• Ask Noah 44: Red Hat with Brandon Johnson
• BSD Now 228: The Spectre of Meltdown