I have been using a standalone Logitech touchpad with my Ubuntu desktop, and trying to pair another one to my backup desktop I learn that both of the Logitech touchpads will not function as a pointing device after being paired, at present time on my Ubuntu 20.04 machines. Not even on the desktop machine where it worked till I unpaired them to narrow down the problem. They are just not acting as pointing devices anymore after pairing/re-pairing them.

I am using Solaar for the pairing.

Here's my solaar output when both touchpads have been re-paired:

$ solaar show
Unifying Receiver
  Device path  : /dev/hidraw1
  USB id       : 046d:c52b
  Serial       : 08C4950C
    Firmware   : 12.10.B0032
    Bootloader : 02.14
    Other      : AA.AA
  Has 2 paired device(s) out of a maximum of 6.
  Notifications: wireless (0x000100)
  Device activity counters: 2=17

  1: Wireless Touchpad
     Codename     : Wireless Touch
     Kind         : touchpad
     Wireless PID : 4011
     Protocol     : HID++ 2.0
     Polling rate : 8 ms (125Hz)
     Serial number: DCBF0037
     The power switch is located on the base.
     Battery: unknown (device is offline).

  2: Wireless Rechargeable Touchpad T650
     Codename     : T650
     Kind         : touchpad
     Wireless PID : 4101
     Protocol     : HID++ 2.0
     Polling rate : 8 ms (125Hz)
     Serial number: E6CBD4AB
     The power switch is located on the base.
     Battery: unknown (device is offline).

This output is after it has been supposedly paired, as one can see from the "Unpair" button on the solaar GUI:

$ solaar --version
solaar 1.0.1

To reiterate, these are touchpads I had successfully acting as pointing devices until un-pairing and re-pairing today.

I got one unifying receiver dongle per each of those touchpads, so I tested all combinations and the problem is the same when trying each of the two unifying receiver dongles. The problem seems consistent across the two touchpad models (one being a T650 the other a built older to recognize now), two logitech unifying receivers and two Ubuntu 20.04 machines.

How would you approach fixing it up so that they actually work as pointing devices after pairing them?

(I'm using X11 and Gnome Shell as the windowing system, on Ubuntu 20.04 with its latest updates installed, in case it matters).

Lately I've been experiencing spontaneous microphone volume level resets to a low level, notably when using Zoom. Sometimes when it happens, I tried resetting alsa:

pulseaudio -k && sudo alsa force-reload

But this oftentimes disconnected the microphone altogether or had no helpful effect at all. I also tried disconnecting and reconnecting the USB cable to no avail.

As I depend on video calls a lot, I have for the first time come close to fantasies about getting a Windows machine just for that, just to say how bad it is. I wonder if this is anything in recent 20.04 software updates, or how would you approach this. I tried switching between two Logitech webcams only to have it reproduce a lot in both. As much as I recall, this type of problem never happened before for me (using these webcams).

In recent days I have noticed that the volume level of the mic resets in the Ubuntu settings application, and then I'm able to pull the mic volume up again to regain normal usage. But then it randomly happens again a few minutes later all over.

I have been tracking a patch for the portaudio library, and I wonder if I'm tracking properly:

Searching launchpad for the version number given by the Debian source (as seen in the link I just mentioned), it looks to me like this patch has been incorporated in the forthcoming Groovy (20.10) release lately, and for the time being not backported to any existing release.

Am I tracking right for such a matter?

And judging by the version numbering scheme (to which I am alien) what could one say, as a speculation, about the odds of this patch making it to already released Ubuntu versions such as the latest LTS (20.04 AFAIK).

Thanks!

Can you control things like viewing angle, zoom, fps, and video resolution for a webcam connected to Ubuntu, through a standard set of commands or API?

As a case in point, the Logitech Brio 4K Ultra HD. This camera seems to be advertised to allow adjustments of those properties that I just mentioned above, and I am wondering whether controlling them is accessible via any standard linux command-line (or standard programming API).

Typically I had good experience with all Logitech devices in Ubuntu but these features I've never experienced adjusting from/in Ubuntu.

Motivation note: I could use these features for acquiring indoors imagery for a machine learning project and the ability to adjust those properties could be important. That aside, these abilities might bear on how much all the sophistication built into this device actually leverages for quality in more mundane use cases like video chat.

I have a machine where due to its history the grub partition sits between two large ext4 partitions, all seen in the picture below. I would like to merge the two partitions which currently sandwich the grub partition (as seen below, one of them is already empty and ready to be re-claimed). So that I'll effectively have one big continuous ext4 partition.

How would I most elegantly and safely move the grub partition and merge the two large partitions which currently surround it?

I found that GParted doesn't offer a way to move the grub partition, at least not when the system is live, and later I found that using GParted from a live USB stick won't allow moving the grub partition either, even though there is a very large unallocated partition (see in the picture again). So I am wondering how to safely and possibly also simply accomplish this in order to better utilize my drive.

Some additional technical details which hopefully do not matter

In case this ties in, this machine should always boot from one partition, all other detectable OS partitions other than its /dev/sda5 are either invalid or completely obsolete. I'd like to move the grub2 partition so that I then can make /dev/sda5, my only boot partition, larger.

And in case it matters, /dev/sda2 is still shown as a boot option in my grub menu even though I've already un-allocated that partition altogether (it's that empty partition right before the grub2 partition in the picture).

Thanks!!

I encounter what appears like bad anti-aliasing or something similar, in the built in PDF viewer and in browsers alike, when switching to portrait mode. All texts just appear oddly fuzzy. Is there a more integrated way of fixing this up so that whenever you change monitor orientation, fonts appear clearly?

I have seen solutions (or should I say partial solutions) mentioned via this question, but would like to be able to switch the monitor orientation now and then depending on the task at hand, without running a multitude of setup commands every time.

I assume this requires integration with the setup screen where display orientation is controlled (Settings → Devices → Displays) in the default Settings app.

I know this might be more like a missing feature request than something that can be done right now without forking the source, but just in case ...

If there's a way, thanks for letting me know!

I have noticed my system is not using any swap.

• system got unresponsive when RAM got full
• swapon --show returns nil
• /etc/fstab has nothing about swap in it

I am utterly confused by the myriad of different ways to enable swap which I read about. Do I really need to define a swap file, rather than only point the system at a swap partition?

I have a partition of the right size formatted as linux-swap. What is the series of steps to be taken for (perpetually) enabling it in my OS?

Ubuntu 16.04

Is there any way for listing file contents in a shell window, such that characters are printed from right to left rather than as usual from the left to the right? or such that the BIDI algorithm steers line direction as per the text present?

This is relevant when working with text files belonging to RTL languages (as well as mixed LTR RTL documents) where you want to grep and search a lot without loading into an editor... editors don't like huge files...

Something around cat could be nice :)

In fact maybe I'll write something that just reverses each line and pipes to cat if nothing known exists.

Can one figure the DVD region/s allowed by their DVD drive?

Note: I mean doing so without trial and error with specific region-encoded DVD's.

$ sudo service cassandra status
● cassandra.service - LSB: distributed storage system for structured data
   Loaded: loaded (/etc/init.d/cassandra; bad; vendor preset: enabled)
   Active: active (running) since Wed 2016-10-12 15:54:40 IDT; 4min 4s ago

What does the bad; part on the 2nd line of the output stand for? I get this for many services, e.g. mysql, winbind, virtualbox, some of which I've flawlessly used already (cassandra being a fresh install).

Please see the edit at the bottom!

I have followed here for adding an item to the launcher. Here are the contents of my new .desktop file:

[Desktop Entry]
Version=1.0
Name=OpenRefine
Comment=2.6-rc.2
Path=/home/foo/openrefine-2.6-rc.2
Exec=/home/foo/openrefine-2.6-rc.2/refine
Terminal=true
Type=Application
Categories=Utility;Application;

(no icon supplied by the application so none included, hopefully a default one will be used). desktop-file-validate passes without errors. So does desktop-file-install. Yet the new program does not show in dash :(

I have started out saving the .desktop file to .local/share/applications, so it is also confusing whether it should remain there after the desktop-file-install or rather it should have been created in some temporary place to begin with, rather than there.

Thanks for clarifying how this should be done.

Edit:

Notably, this program, OpenRefine, when started in a terminal, does not open a UI window. It only starts a web server and launches the default browser against it.

I installed Ubuntu 16 desktop a few weeks ago. Added Chrome and all fine. However now when I try sudo apt-get install ffmpeg, I get this error message:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 google-chrome-stable : Depends: libappindicator1 but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

What's the problem and what should I do?

I might need to add a graphics card to my computer, for connecting a 3rd monitor. Is that supposed to work? what configuration will I have to make so that two (Nvidia) graphics cards are used for display, if that is at all possible? doesn't seem to work after installing the second card in the box:

• Attempt 1 details

• Attempt 2 details

Cards I am using are both model GT730

Binding keyboard shortcuts in Keyboard > Shortcuts > Launchers, to "special keyboard keys" like the Home, Search, Mail buttons etc., does not work on a new desktop (14.04.1), but did work on the former (14.04).

I can get those special keys of my keyboard (Microsoft Natural Ergonomic 7000) correctly identified when clicking them inside that settings screen, indicating the keys are recognized. However they do not in practice produce the "Launch" effect I have assigned to them there in that settings screen.

Rather, the mouse pointer just disappears when they are clicked (and shows again when the mouse is moved).

Oddly enough, they do get captured e.g. in Chrome, with their default Chrome behavior, but not by the desktop as expected by my settings.

Fiddling ls -l /dev/input/by-id and then sudo evtest /dev/input/.. I can notice these keys go through an event sink that is shared with mouse events, unlike those of ordinary keys on my keyboard.

I'm unsure:

1. Why does this affect the desktop launchers, but not Chrome.. is Chrome just written better?
2. Can I somehow avoid this?

Any ideas?

With many new hard drive disks the physical sector size is 4096. Would it be possible to make the system use a logical sector size of the same size, rather than the default logical sector size of 512?

How would you configure that?

On ubuntu 14.04 how do you check if TRIM is on for an SSD drive? Other settings worth verifying for an SSD drive?

Which parts of Ubuntu would you offload from an SSD installed system to HDD or vice versa, to reduce write cycles and still enjoy better responsiveness?

I assume the following, but must be missing quite a bunch.

1. swap partition - unless you really think your SSD will survive long
2. /tmp
3. any database data directories
4. things that keep updating like ~/Downloads and other user login session directories

Or is it easier to say what to keep on SSD rather than what to move away... basically I think for SSD longevity per-se, it would make sense to only store programs on SSD and data that is pretty much constant. Is there at all a sensible way to map out the default Ubuntu (Desktop) directories structure by this criteria?

Ubuntu 14.04 LTS.

How do you nicely stop all postgres processes with pg_ctl (or otherwise), when you don't recall what the database directory is, nor have the PGDATA environment variable defined?

I would like to reformat a local drive partition and turn it into a partition for HDFS. Which file system would be most performant for running HDFS on top of it? Any optimizations I should take care of for this file system?

This is an Ubuntu 14.04

I am considering enabling the ring switcher (or other) effects that come along with compiz extras on my Ubuntu 13.10. The default app switcher is not that much to my liking - navigating multiple windows of a same app is clumsy as hell and overall it's very old school.

So when I am about to add the ring switcher to replace the default alt-tab behavior, an intimidating :) question about whether I choose to ignore or resolve conflicts show up. Would there be a way for me to reset all this setup back from the command-line in case that renders my server desktopless as some people have reported about other kinds of compiz fiddling? there's a whole slew of stuff at How can I reset Compiz settings to default? and I really wonder which of them is the clean way if any.

Also will applying this change still be safe once I'd upgrade to the future Ubuntu 14.04?