Linux

Ubuntu Podcast from the UK LoCo: S11E19 – Nineteen Minutes - Ubuntu Podcast

Planet Ubuntu - 5 hours 28 min ago

This week we recover from a failed disk in a ReadyNAS and get to grips with the Amazon Kindle Oasis E-reader. npm gets pwned, Debian 9.5 is released, the Snap Store get verified publishers, categories and other improvements. Humble Bundle offer a Linux Geek Book Bundle, we also round up the community news and events.

It’s Season 11 Episode 19 of the Ubuntu Podcast! Alan Pope, Mark Johnson and Ryan are connected and speaking to your brain.

In this week’s show:

That’s all for this week! You can listen to the Ubuntu Podcast back catalogue on YouTube. If there’s a topic you’d like us to discuss, or you have any feedback on previous shows, please send your comments and suggestions to show@ubuntupodcast.org or Tweet us or Comment on our Facebook page or comment on our Google+ page or comment on our sub-Reddit.

Categories: Linux

Simon Raffeiner: Improving data safety on Linux systems using ZFS and BTRFS

Planet Ubuntu - Tue, 07/17/2018 - 07:20

Why everybody should you care about data safety, and how ZFS and BTRFS can help protect the data on your Linux systems.

The post Improving data safety on Linux systems using ZFS and BTRFS appeared first on LIEBERBIBER.

Categories: Linux

Sergio Schvezov: New Laptop

Planet Ubuntu - Tue, 07/17/2018 - 06:50
Triggers Recently, as of last week, I decided to purchase a new laptop to replace my Microsoft Surface Pro 4 with which I was having a bittersweet relationship. The Surface Pro 4 is really nice hardware, I originally got it to get a head start and collaborate on the convergence story with Unity 8 on the desktop, but as is of folk knowledge now, some strategic choices were made.
Categories: Linux

David Tomaschik: Useful Metasploit Reminders

Planet Ubuntu - Mon, 07/16/2018 - 21:52

This isn’t an intro to metasploit, but more a reminder to myself of things that are useful to know, but maybe not used all the time (or relatively new).

Meterpreter
Categories: Linux

David Tomaschik: Synonyms in x86 Assembly

Planet Ubuntu - Mon, 07/16/2018 - 21:52

I recently had an opportunity to handcraft shellcode with unusual restrictions, and appreciated that there’s a number of ways to accomplish any goal in an ISA as flexible as x86. (Most of these techniques will apply to x86-64 as well, but the work I was doing happened to be 32 bit, so that’s what I will use as an example.) Obviously, this won’t be comprehensive, but it’s just a reminder of different ways you can do something. If you ever think it’s impossible, remember to try harder.

Most of my examples will use eax, unless a special circumstance applies (i.e., dealing with esp, eip, etc.). They’re not all going to be strictly synonyms, because many of them will have varying side effects (flags, etc.). I will try to note any that have potentially undesirable side effects like clobbering other registers, leaving the stack modified, etc.

Zero Out a Register 1 mov eax, 0

Straight out zero: has the disadvantage of sticking a bunch of NULL bytes in your output, which is a problem for many use cases.

1 xor eax, eax

Because a^a=0, xoring a register with itself clears it. Nice and short (2 bytes) and no NULL bytes.

1 shl eax, 32

This works by zero-filling of shifts.

1 2 mov eax, -1 not eax

This sets eax to 0xFFFFFFFF, then inverts it.

1 2 mov eax, -1 inc eax

Similarly to above, but it increments rather than inverts eax.

Categories: Linux

The Fridge: Ubuntu Weekly Newsletter Issue 536

Planet Ubuntu - Mon, 07/16/2018 - 14:58

Welcome to the Ubuntu Weekly Newsletter, Issue 536 for the week of July 8 – 14, 2018. The full version of this issue is available here.

In this issue we cover:

The Ubuntu Weekly Newsletter is brought to you by:

  • Krytarik Raido
  • Bashing-om
  • Chris Guiver
  • And many others

If you have a story idea for the Weekly Newsletter, join the Ubuntu News Team mailing list and submit it. Ideas can also be added to the wiki!

Except where otherwise noted, this issue of the Ubuntu Weekly Newsletter is licensed under a Creative Commons Attribution ShareAlike 3.0 License

Categories: Linux

Colin King: Comparing Latencies and Power consumption with various CPU schedulers

Planet Ubuntu - Mon, 07/16/2018 - 05:31
The low-latency kernel offering with Ubuntu provides a kernel tuned for low-latency environments using low-latency kernel configuration options.  The x86 kernels by default run with the Intel-Pstate CPU scheduler set to run with the powersave scaling governor biased towards power efficiency.

While power efficiency is fine for most use-cases, it can introduce latencies due to the fact that the CPU can be running at a low frequency to save power and also switching from a deep C state when idle to a higher C state when servicing an event can also increase on latencies.

In a somewhat contrived experiment, I rigged up an i7-3770 to collect latency timings of clock_nanosleep() wake-ups with timer event coalescing disabled (timer_slack set to zero) over 60 seconds across a range of CPU scheduler and governor settings on a 4.15 low-latency kernel.  This can be achieved using stress-ng, for example:

sudo stress-ng --cyclic 1 --cyclic-dist 100 –cyclic-sleep=10000 --cpu 1 -l 0 -v \
--cyclic-policy rr --cyclic-method clock_ns --cpu 0 -t 60 --timer-slack 0

..the above runs a cyclic measurement collecting latency counts in 100ns buckets with a clock_nanosecond wakeup interval of 10,000 nanoseconds with zero % load CPU stressor and timer slack set to 0 nanoseconds.  This dumps latency distribution stats that can be plotted to see where the modal latency points occur and the latency characteristics of the CPU scheduler.

I also used powerstat to measure the power consumed by the CPU package over a 60 second interval.  Measurements for the Intel-Pstate CPU scheduler [performance, powersave] and the ACPI CPU scheduler (intel_pstate=disabled) [performance, powersave, conservative and ondemand] were taken for 1,000,000 down to 10,000 nanosecond timer delays.

1,000,000 nanosecond timer delays (1 millisecond) Strangely the powersave Intel-Pstate is using the most power (not what I expected).

The ACPI CPU scheduler in performance mode has the best latency distribution followed by the Intel-Pstate CPU scheduler also in performance mode.

100,000 nanosecond timer delays (100 microseconds)Note that Intel-Pstate performance consumes the most power...
...and also has the most responsive low-latency distribution.

10,000 nanosecond timer delays (10 microseconds)
In this scenario, the ACPI CPU scheduler in performance mode was consuming the most power and had the best latency distribution.

It is clear that the best latency responses occur when a CPU scheduler is running in performance mode and this consumes a little more power than other CPU scheduler modes.  However, it is not clear which CPU scheduler (Intel-Pstate or ACPI) is best in specific use-cases.

The conclusion is rather obvious;  but needs to be stated.  For best low-latency response, set the CPU governor to the performance mode at the cost of higher power consumption.  Depending on the use-case, the extra power cost is probably worth the improved latency response.

As mentioned earlier, this is a somewhat contrived experiment, only one CPU was being exercised with a predictable timer wakeup.  A more interesting test would be with data handling, such as incoming packet handling over ethernet at different rates; I will probably experiment with that if and when I get more time.  Since this was a synthetic test using stress-ng, it does not represent real world low-latency scenarios, however, it may be worth exploring CPU scheduler settings to tune a low-latency configuration rather than relying on the default CPU scheduler setting.
Categories: Linux

Lubuntu Blog: This Week in Lubuntu Development #7

Planet Ubuntu - Sun, 07/15/2018 - 23:40
Here is the seventh issue of This Week in Lubuntu Development. You can read the last issue here. Changes General This week was focused on polishing the installer experience and the desktop in general. Here are the changes made, with links to the full details. Lubuntu Artwork Rename sddm-theme-lubuntu-chooser to sddm-theme-lubuntu. Since Ubuntu's sddm is […]
Categories: Linux

Robert Ancell: GUADEC 2018 Almería

Planet Ubuntu - Sun, 07/15/2018 - 20:41
I recently attended the recent GNOME Users and Developers European Conference (GUADEC) in Almería, Spain. This was my fifth GUADEC and as always I was able to attend thanks to my employer Canonical paying for me to be there. This year we had seven members of the Ubuntu desktop team present. Almería was a beautiful location for the conference and a good trade for the winter weather I left on the opposite side of the world in New Zealand.

This was the second GUADEC since the Ubuntu desktop switched back to shipping GNOME and it’s been great to be back. I was really impressed how positive and co-operative everyone was; the community seems to be in a really healthy shape. The icing on the cake is the anonymous million dollar donation the foundation has received which they announced will be used to hire some staff.

The first talk of the week was from my teammates Ken VanDine, Didier Roche and Marco Treviño who talked about how we’d done the transition from Unity to GNOME in Ubuntu desktop. I was successful in getting an open talk slot and did a short talk about the state of Snap integration into GNOME. I talked about the work I’d done making snapd-glib and the Snap plugin in GNOME Software. I also touched on some of the work James Henstridge has been working on making Snaps work with portals. It was quite fun to see James be a bit of a celebrity after a long period of not being at a GUADEC - he is the JH in JHBuild!

After the first three days of talks the remaining three days are set for Birds of a Feather sessions where we get together in groups around a particular topic and discuss and hack on that. I organised a session on settings which turned out to be surprisingly popular! It was great to see everyone that I work with online in-person and allowed us to better understand each other. In particular I caught up with Georges Stavracas who has been very patient in reviewing the many patches I have been working on in GNOME Control Center.

I hope to see everyone again next year!
Categories: Linux

Ubuntu Podcast from the UK LoCo: S11E18 – Eighteen Summers - Ubuntu Podcast

Planet Ubuntu - Thu, 07/12/2018 - 08:00

This week we’ve been using GameMaker 1.4 on Windows to patch Spelunky for Linux. We interview some of the Ubuntu Communitheme team, round up the community news and go over your feedback.

It’s Season 11 Episode 18 of the Ubuntu Podcast! Alan Pope and Martin Wimpress are connected and speaking to your brain.

In this week’s show:

That’s all for this week! You can listen to the Ubuntu Podcast back catalogue on YouTube. If there’s a topic you’d like us to discuss, or you have any feedback on previous shows, please send your comments and suggestions to show@ubuntupodcast.org or Tweet us or Comment on our Facebook page or comment on our Google+ page or comment on our sub-Reddit.

Categories: Linux

Jono Bacon: Video: Building Community Leaders: A Guide

Planet Ubuntu - Tue, 07/10/2018 - 17:35

Recently I gave a keynote at DevXCon in San Francisco. So, what better place to deliver a presentation that is entirely non-technical and non-specific to developer relations?

“You are bonkers, Bacon”, I hear you say.

Well, hold your horses. Effective leadership, how we identify quality leaders, and how we foster great leadership at scale is critical to all communities. As such, I took a crack at this topic in my keynote. Fortunately, it seemed well-received by the folks there.

Now it is your turn to decide. Here is the video:

Can’t see the video? Click here.

I would love to hear your ideas about what great leadership consists of and how you have approached this. Share your thoughts in the comments!

The post Video: Building Community Leaders: A Guide appeared first on Jono Bacon.

Categories: Linux

Kubuntu General News: KDE Plasma bugfix release 5.12.6 is now available for Kubuntu 18.04 LTS

Planet Ubuntu - Tue, 07/10/2018 - 08:47

The Kubuntu Community is please to announce that KDE Plasma 5.12.6, the latest bugfix release for Plasma 5.12 was made available for Kubuntu 18.04 LTS (the Bionic Beaver) users via normal updates.

The full changelog for 5.12.6 contains scores of fixes, including fixes and polish for Discover and the desktop.

These fixes should be immediately available through normal updates.

The Kubuntu team wishes users a happy experience with the excellent 5.12 LTS desktop, and thanks the KDE/Plasma team for such a wonderful desktop to package.

Categories: Linux

Balint Reczey: Run Ubuntu on Windows, even multiple releases in parallel!

Planet Ubuntu - Mon, 07/09/2018 - 13:50

Running Linux terminals on Windows needs just a few clicks since we can install Ubuntu, Debian and other distributions right from the Store as apps, without the old days’ hassle of dual-booting or starting virtual machines. It just works and it works even in enterprise environments where installation policies are tightly controlled.

If you check the Linux distribution apps based on the Windows Subsystem for Linux technology you may notice that there is not only one Ubuntu app, but there are already three, Ubuntu, Ubuntu 16.04 and Ubuntu 18.04. This is no accident. It matches the traditional Ubuntu release offering where the LTS releases are supported for long periods and there is always a recommended LTS release for production:

  • Ubuntu 16.04 (code name: Xenial) was the first release really rocking on WSL and it will be updated in the Store until 16.04’s EOL, April, 2021.
  • Ubuntu 18.04 (code name: Bionic) is the current LTS release (also rocking :-)) and the first one supporting even ARM64 systems on Windows. It will be updated in the Store until 18.04’s EOL, April, 2023.
  • Ubuntu (without the release version) always follows the recommended release, switching over to the next one when it gets the first point release. Right now it installs Ubuntu 16.04 and will switch to 18.04.1, on 26th July, 2018.

The apps in the Store are like installation kits. Each app creates a separate root file system in which Ubuntu terminals are opened but app updates don’t change the root file system afterwards. Installing a different app in parallel creates a different root file system allowing you to have both Ubuntu LTS releases installed and running in case you need it for keeping compatibility with other external systems. You can also upgrade your Ubuntu 16.04 to 18.04 by running ‘do-release-upgrade’ and have three different systems running in parallel, separating production and sandboxes for experiments.

What amazes me in the WSL technology is not only that Linux programs running directly on Windows perform surprisingly well (benchmarks), but the coverage of programs you can run unmodified without any issues and without the large memory overhead of virtual machines.

I hope you will enjoy the power or the Linux terminals on Windows at least as much we enjoyed building the apps at Canonical working closely with Microsoft to make it awesome!

Categories: Linux

The Fridge: Ubuntu Weekly Newsletter Issue 535

Planet Ubuntu - Mon, 07/09/2018 - 13:37

Welcome to the Ubuntu Weekly Newsletter, Issue 535 for the week of July 1 – 7, 2018. The full version of this issue is available here.

In this issue we cover:

The Ubuntu Weekly Newsletter is brought to you by:

  • Krytarik Raido
  • Bashing-om
  • Chris Guiver
  • And many others

If you have a story idea for the Weekly Newsletter, join the Ubuntu News Team mailing list and submit it. Ideas can also be added to the wiki!

Except where otherwise noted, this issue of the Ubuntu Weekly Newsletter is licensed under a Creative Commons Attribution ShareAlike 3.0 License

Categories: Linux

Stephen Michael Kellat: Switching Things Up

Planet Ubuntu - Sun, 07/08/2018 - 22:33
What Happened?

Things are getting a bit troublesome at work. I have been getting sick a bit more frequently. We've been having more people showing up with "pulse-ox" meters to see if they're even getting enough oxygen to breath. The air isn't that great in my section. With the increasing pace of retirements being announced, I suppose I need to recognize the handwriting that is on the wall.

Besides, have you seen the federal cabinet ministers getting harassed while simply trying to eat dinner? Secretaries of Homeland Security and Transportation, the now-former EPA Administrator, and the Assistant to the President/Press Secretary have all run into a spot of bother. This is not behavior to encourage.

Now What?

A project proposal being passed around at church is for me to stand up an adult education/pre-college unit. Our local school district doesn't always have the best graduation outcomes. In this instance I would be standing up an experimental operation to work during the fall to offering some remedial education for local students as well as "pre-college preparatory experiences".

In short, do tutoring as well as some lecturing on how to ensure 2+2=4 plus also working on reading. I do have a degree in library science that is barely used so working on the literature aspect would be fairly simple. Chalkboards and chalk are already there as well as tables and chairs. Facilities would be put to use during downtime between services. Dragging in resources from Saylor Academy would also be useful to ensure students could actually pick up credits from an external provider through things like The Alternative Credit Project. For those operating from a Christian viewpoint, Acts 8:26-40 is the scriptural example we're working with that also potentially includes students working with MOOCs too. History doesn't repeat but it sure can look awfully similar.

The big problem is that this would be incompatible with at least 1 of the 3 sets of ethics rules I have to comply with as a federal civil servavnt. To do this, I would have to leave the federal civil service. Then again, for the sake of my own personal safety this is probably the best time ever to do so.

To maintain subsistence on half pay for the remainder of calendar year 2018, I would have to raise USD$10,000. Thankfully this is not something that would be dealt with via Patreon or the like which would otherwise requiring me wading through the IRS Sharing Economy Tax Center for guidance. The church is a 501(c)(3) entity and would be the fiscal agent.

Since the congregation is older than ARPANet and still has a halting embrace of technology, there's very little computer technology in use there. There is no website. There is no e-mail address. Checks/cheques are still good and still useful for making donations that are tax-deductible in the United States. There is a full document known as Publication 526 from the IRS that details how that works if somebody wanted to make a donation to help further this work.

I thought logistically about PayPal and all sorts of other platforms. They do great for what they're intended to do although they end up putting money in my lap in a way that isn't tax-deductible. It doesn't go directly to the church first and winds up running things through the IRS Sharing Economy Tax Center again. They actually overcomplicate things as well as introduce arbitrage fees and other unnecessary weirdnesses. From the Publication 526 perspective, all that needs to happen is that a church get a check or other instrument like a money order to deposit so it can then turn around and send an acknowledgement letter which can then be used as a potential tax write-off.

Are There Timeframes For This?

Yes, of course. The goal is to be able to walk away from my current job by no later than July 20th. I would be then spending 20 hours per week working on this matter for the church in addition to the limited missionary-preacher work I do twice per month. Getting at least USD$3,000 raised by then would ensure at least two months funds were on-hand to keep me at subsistence operating. That is to say, keeping a roof over my head and food on the table.

The goal would be to have students start trickling in before Labor Day. Locally the K-12 students will already be back in sessions around August 20th so we can start promoting available services then. We'd take it from there and expect to wrap up with any participating students by no later than December 14th.

To discuss how to donate and to coordinate any funding participation, feel free to send an e-mail to ashtabulaeducationproject@gmail.com.

With luck I may be able to do some good in my local community. I've been fueling the engine of the nation-state long enough. Change seems to be in the winds.


Switching Things Up by Stephen Michael Kellat is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Based on a work at https://identi.ca/alpacaherder/note/8h47hl0DTR2tfkJ1oBqdXg.

Categories: Linux

Costales: Podcast Ubuntu y otras hierbas S02Extra2: Entrevista a Alberto Larraz, organizador de Obrim el Codi

Planet Ubuntu - Sat, 07/07/2018 - 02:51
En esta ocasión, Francisco Javier Teruelo y Marcos Costales, entrevistamos a Alberto Larraz, profesor, organizador del evento que se celebró hace un mes en Barcelona: Obrim el Codi.

2º Capítulo Extra de la segunda temporada
El podcast esta disponible para escuchar en:
Categories: Linux

Lubuntu Blog: This Week in Lubuntu Development #6

Planet Ubuntu - Thu, 07/05/2018 - 19:28
Here is the sixth issue of This Week in Lubuntu Development. You can read the last issue here. Changes Lubuntu 17.10 reaches End of Life on July 19, 2018 Following the announcement from Adam Conrad, we are announcing that Lubuntu 17.10 reaches End of Life on July 19, 2018. After July 19, Lubuntu 17.10 will […]
Categories: Linux

Launchpad News: Launchpad news, June 2018

Planet Ubuntu - Thu, 07/05/2018 - 18:18

Here’s a brief changelog for this month.

Bugs
  • Handle Bugzilla.time() changes in Bugzilla 5.1.1 (#1774838)
  • Cope with the comment author field being renamed to creator in recent Bugzilla versions (#1774838)
Build farm
  • Set the hostname and FQDN of LXD containers to match the host system, though with an IP address pointing to the container (#1747015)
  • If the extra build arguments include fast_cleanup: True, then skip the final cleanup steps of the build; this can be used when building in a VM that is guaranteed to be torn down after the build
  • Allow checking out a git tag rather than a branch (#1687078, forum post)
  • Add a local unauthenticated proxy on port 8222, which proxies through to the remote authenticated proxy; this should allow running a wider range of network clients, since some of them apparently don’t support authenticated proxies very well (#1690834, #1753340, forum post)
  • Run tar with correct working directory when building source tarballs for snaps
Code
  • Port the loggerhead (Bazaar code browser) integration to gunicorn, allowing it to be used as an internal API as well
  • Optimise BuildableDistroSeries.findSeries (#1778732)
  • Proxy loggerhead branch diffs through the webapp, allowing AJAX MP revision diffs to work for private branches (#904070)
Infrastructure
  • Convert most code to use explicit proxy configuration settings rather than picking up a proxy from the environment, making the effective production settings easier to understand
Registry
  • Fix crash while adding an ssh key with unknown type (#1777507)
Miscellaneous
  • Improve documentation of what deactivating an account does (#993153)
Categories: Linux

Ubuntu Podcast from the UK LoCo: S11E17 – At Seventeen - Ubuntu Podcast

Planet Ubuntu - Thu, 07/05/2018 - 08:00

This week we make a snap of Xonotic, interview Daniel Foré from elementary OS about the Beta release of “Juno” and round up the news.

It’s Season 11 Episode 17 of the Ubuntu Podcast! Alan Pope and Martin Wimpress are connected and speaking to your brain.

In this week’s show:

That’s all for this week! You can listen to the Ubuntu Podcast back catalogue on YouTube. If there’s a topic you’d like us to discuss, or you have any feedback on previous shows, please send your comments and suggestions to show@ubuntupodcast.org or Tweet us or Comment on our Facebook page or comment on our Google+ page or comment on our sub-Reddit.

Categories: Linux

Marco Trevisan (Treviño): I’m going to GUADEC (with Ubuntu Desktop team)!

Planet Ubuntu - Wed, 07/04/2018 - 11:28

Hi Folks,

I’m writing these lines while I’m in the flight to Almeria where this year’s GNOME Users And Developers European Conference will take place, typing with my Thinkpad Bluetooth keyboard on my mobile phone (I’ve to admit that the Android physical keyboard usage is getting awesome, allowing proper WM actions) :), as the battery of my T460p was already over after the flight from Florence to Madrid during which I fixed some more shell JS errors.

This will be my first GUADEC ever, and as a fresh Foundation member, I’m quite excited to finally join it.

I’m not coming alone, of course, as this year the ubuntu-desktop team will be quite crowded, as me, Ken VanDine, Sébastien Bacher, Didier Roche, Iain Lane, James Henstridge and Robert Ancell will be part of the conference, to give input and help to get GNOME even better.

Soo, looking forward to meet you all very soon (almost landed – or better – trying to, in the mean time)!

As always, I’ve to thank Canonical for allowing me and the desktop crew to be part of this great community reunion. But also for being one of the silver sponsors of the event.

These are the events that really matter in order to get things done.

Categories: Linux

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