Score: 0
Nicholas Saunders avatar
how to start the snap install of tomcat?
mx flag

How is the tomcat server started?

nicholas@mordor:~$ sudo systemctl start tomcat
Failed to start tomcat.service: Unit tomcat.service not found.
nicholas@mordor:~$ sudo systemctl enable tomcat
Failed to enable unit: Unit file tomcat.service does not exist.
nicholas@mordor:~$ snap info tomcat-with-ssl
name:      tomcat-with-ssl
summary:    ...
Score: 4
Emanuele avatar
BCM4352 802.11ac Wireless Network Adapter not working on kernel 5.11 and ubuntu 20.04
cn flag

Right now it works with kernel 5.8 but in 5.11 (installed this morning along other upgrades) the wifi adapter doesn't get detected at all and apparently there are no fixes until the drivers gets patched (unless i'm mistaken). Do someone know if/when bcmwl-kernel-source will get patched?

edit: current version of bcmwl-kernel-source is

PS: To be honest each time there's a ke ...

Score: 0
oakpep avatar
Can't update GRUB
us flag

Yesterday I enlarged the system partition using gparted. Everything went fine, I rebooted and everything worked. This morning after turning on and selecting linux from bootlader - it does not turn on. I read that I should update GRUB, I use boot-repair with live-usb for this. Unfortunately the operation failed I'm getting these errors.

I also tried to repair and reinstall grub using a live USB accordi ...

Score: 2
ikegami avatar
do-release-upgrade silently fails upgrading from 18.04 LTS to 20.04 LTS in WSL
ru flag

It's high time I upgrade Ubuntu from 18.04 to 20.04! But I don't get very far before the process aborts without an error message. Is there a log file I can check for further information?

$ uname -a
Linux tribble 5.4.72-microsoft-standard-WSL2 #1 SMP Wed Oct 28 23:40:43 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubunt ...
Score: 0
8bit avatar
Create own filter for fail2ban fails
kr flag

I'm playing around with fail2ban in kubernetes. For that I created a pod that creates fake log messages: 2021-08-04 18:33:13 Authentication failed I created a custom filter, to test if fail2ban is working. I first tried the fail2ban-regex util with a file containing 10 lines of these log messages and got this output:

Running tests

Use   failregex filter file : test, basedir: ...
Score: 1
akaoru avatar
How does Syndrome-Trellis Code (STC) work?
mx flag

Syndrome-trellis code was introduced to minimize embedding distortion in steganography. See this paper: Minimizing Embedding Impact in Steganography using Trellis-Coded Quantization.

Background information

The following paragraph can be found on this website:

Syndrome-trellis codes are essentially binary linear convolutional codes represented by parity-check matrix. This representation allows to us ...

Score: 0
Marshhh avatar
GRUB and system boot order not detecting Windows
es flag

Recently, I tried to dual boot Ubuntu alongside windows 10. I didn't have free space on my windows partition, i.e, C:, so, made a partition in the D: drive and installed Ubuntu on it. I ran into several problems, like after turning on my laptop, my screen continuously showed No Boot device found. Hence, I tried to go into boot order settings by pressing F9 and my system was able to boot into Ubuntu by B ...

Score: 0
user241990 avatar
sudo apt-get update failed to Cannot initiate the connection to, where able to perform apt-get update root
cn flag

Am using ubuntu 20.04, where using proxy to connect internet.

Able to perform "apt-get update" as "root"

where not able to perform "apt-get update" && apt-get install vnc" as non-root user with sudo prefix

Score: 1
koyakun avatar
Why do Japanese keyboard arrow keys scroll in LibreOffice Calc but move cell with US keyboard layout?
cn flag

After upgrading to Ubuntu 21.04, the arrow keys on my USB Japanese 108-key keyboard scroll in LibreOffice Calc as though scroll lock is toggled on (even though the scroll lock light is not on) instead of moving the selected cell. (Actually, this happens with the US-intl keyboard layout too.) The arrow keys work as expected in other programs though, including LibreOffice Writer.

If I switch to the ...

Score: 0
REZ amer avatar
Is there a specific control panel for intel HD graphics in Ububtu
us flag

I have and Intel HD Graphics (1st gen) (ironlake)

Score: 0
pvdb avatar
How to change the Microsoft account for OneDrive in Ubuntu
lk flag

I have installed onedrive (version v2.4.13-9-g7857a50) on Ubuntu 20.04 LTS.

After using my (test) microsoft account I want to use my "production" microsoft account.

I did the following : rename ~/.config/onedrive/refresh_token into refresh_token_backup and removed the originale file. After starting Onedrive it still uses my test MS-account.

Have someone a solution for me ?

rgds pvdb

Score: 0
El Señor Gato avatar
Problems updating Kubuntu 20.04.02 Focal Fossa - Many error messages
lb flag

I have a problem updating my system. For some reason error messages are being displayed in Spanish even though I don't use it.

This is the error message what I got in terminal

E: El repositorio «cdrom://Kubuntu LTS _Focal Fossa_ - Release amd64 (20210209.1) focal Release» no tiene un fichero de Publicación.
N: No se puede actualizar de un repositorio como este de forma segura y por tanto  ...
Score: 2
mahen3d avatar
SELinux - blocks postfix emails sending out from the Web Application
cn flag

My System environment, is Centos-7.9, Apache2.4, Php-fpm, PHP-7.4

I have postfix setup to send emails from the website, which is working in stand-alone test emails and when I turn the SELinux off.

However, if SELinux is enabled it will block sending the emails out from the server with below error in the /var/log/maillog

 postfix/sendmail[10883]: fatal: execv /usr/libexec/postfix/smtpd: Permission  ...
Score: -1
View with multiple blocks, how to specify which is shown?
ph flag

I have a view that is placed as a block below my main content. Within that view I have block "displays". each having a different contextual filter for their id from url.

The problem is when the view is displayed, it only shows one of the Displays, how do i specify which is shown ?

enter image description here

Score: 0
anVzdGFub3RoZXJodW1hbg avatar
Mount S3FS mount to EFS additionally and share to other Kubernetes pod
es flag

What I need to achieve that is almost done without the EFS/S3FS share:

  1. SFTP pod used by some microservices that process content and deliver back processed content have sftp users that go to tenant specific paths (e.g. tenant-1, tenant-2) through SFTP, these chrooted paths are mounted to different EFS points through EFS provisioner.

  2. Tenant pod - each mounting /var/s3fs <-> S3FS S3 bucket. A ...

Score: 3
user2357 avatar
What does it mean: Hardware vs software implementation of a cryptosystem
us flag

While reading some cryptography papers, I passed by some new terms like the hardware and software implementation of encryption systems.

The question: what are the hardware and the software implementations of encryption systems? And what is the difference between them?

Score: 0
How to view which packages /files where updated last and when, is there a list online?
cz flag

I'm running Ubuntu 20.04 and I'm trying to find out which packages and files where updated/changed last and when on a machine, also is there a list online that says which packages are the latest for an LTS and what was changed?

I know about

cat /var/log/dpkg.log | grep "\ install\ "

and it gives me

2021-08-03 11:30:12 install libjcat1:amd64 <none> 0.1.3-2~ubuntu20.04.1
2021-08-03 11:30:18 inst ...
Score: 0
nautanasgiseda avatar
USB/SATA cable simply does not work on Ubuntu
al flag

I couldn't find an answer to my problem because all other similar questions have Ubuntu properly recognize the external HDD as a storage medium and assign it to /dev/sdb. If only it were this easy. It doesn't matter what HDD I plug into the cable, Ubuntu just does not recognize it. A /dev/sd[x] link is never assigned to it. lsusb lists the drive as ID 1234:5678 Brain Actuated Technologies VLI Prod ...

Score: 0
Mippi avatar
Problem with installation of nvidia driver 340 after last update ubuntu 20.04
cn flag

After yesterday update of Ubuntu 20.04, I am not able to install nvidia driver 340 and all Ubuntu systems with driver 340 crashed:( Has somebody met the same problem? Is there any simple and quick solution? All suggestions are very welcome.

I have Nvidia Quadro NVS 295. The systems have worked for last two years without any problem. Since last update All are crashed.

I tried to reinstall one of them ...

Score: 0
Dupre avatar
Can a VPN service be used like a reverse VPN allowing inbound traffic for serving a website?
sy flag

I’ve done quite a bit of searching, and it seems this can be done, but the answers I seem to find are either vague or responses are something along the lines of “but why would you want to do that?”

I’m hoping someone can point me in the right direction to accomplish the following:


Visitor - > Cloudflare Proxy -> Web Server

Cloudflare DNS proxy sits in front of my web ser ...

Score: 0
Whip avatar
Fail2ban exited and didn't start back up
cn flag

Today I faced a what seemed like a DDOS attack. My server provider warned me about excessive CPU usage (400% for over 6 hours) and I couldn't access any website, could not login via SSH either. Lish console reported an error that went something like 'php-fpm out of memory'.

Only thing I could do was a hard reboot. After server was up again, I looked at fail2ban's status and it shows 'active(exite ...

Score: 0
ss_everywhere avatar
HDD not installed after Ubuntu install Ideapad 15ALC05
cn flag

I got an brand new 15ALC05 (ryzen 7) and tried to setup ubuntu( LTS)  dual boot using a bootable usb drive. After successful installation when I tried to restart I get the boot menu with Windows boot manager, Ubuntu and Setup. The only option that works is "Setup" that takes me to Bios setup.   Also in the Information tab in the Bios setup I see "HDD : Not installed".   I called up Lenovo su ...

Score: -1
Rented Dreams avatar
Trying to resurrect 10 year old software - can't activate Windows Server 2008 R2 and problems with Activate by Phone
je flag

I wrote a workshop database application for a client in Romania that had a Land Rover dealership a long long time ago in Access 2.0. Haven't heard from him in years, then last week he calls. He is still using the program ! and want me to "update" it.

Thank goodness for old MSDN library CD folders in back of file cabinets. So, I have installed an old copy of Win Server 2008 R2 Enterprise and load ...

Score: 0
woosley. xu avatar
Port numbers reused after Reset
mx flag

Recently in our production Kubernetes cluster, we saw a lot of outbound reset connection, after some troubleshooting, we have below network flow captured.

Network Capture

we are really confused by this flow. in this flow.

  1. from localport 33890, a new connection is created and sync packet is send out
  2. for whatever reason, remote reset this connection.

then here comes the confusing part, all sync packs s ...

Score: 3
thzoid avatar
Proof that a message is signed by a member of a group
ng flag

I'm a newbie at cryptography. Here is my question:

  1. Alice makes a list of people: Bob, Carol and Dan;
  2. Alice gives a unique secret key to every member on the list, so they can uniquely sign messages;
  3. Each member has no right to sign more than 1 message;
  4. Grace, an observer, needs to be able to check whether a certain message was signed by a member of Alice's list, but she must not know who signed it.
  5.  ...
Score: 1
Mike DeSimone avatar
How to reduce/restrict resolution on startup
tr flag

I've got an old Intel Haswell NUC using onboard Intel graphics connected to a new LG monitor with a native resolution of 1920x1080 on the HDMI port.

However, on startup (right after Grub hands off to the kernel, before the "Ubuntu" screen shows up with the spinny triskelion thing) the system decides to change the resolution to 3840x2160 at 30 Hz, which the screen resamples down to its native 1920 ...

Score: 0
kws3778 avatar
Screen flickering after upgrade to Ubuntu 20.04
za flag

I recently upgraded from Ubuntu 18.04 to 20.04 LTS on my laptop (Lenovo Ideapad FLEX 6-14IKB). After a while the screen would start flickering (similar to the video in this post here). I notice that sometimes it would flicker a lot an then stop for a while - it would usually happen more often when I'm actively browsing Chrome/Firefox. The issue does not exist on an external monitor that I connect ...

Score: 0
I get a block that doesn't change on other pages
us flag

I have an issue with the contextual filters when I use Content: ID. On the site I get a repetitive, when there are many more recipes.

The block remains the same, with two recipes, which is fine, but they don't change on another page. It's always the same.

I hope this makes sense.



Contextual Filter


Main Issue

Score: 0
Tameni Rahman avatar
How can I increase trackpad sensitivity?
kr flag

I am new to Linux and downloaded Ubuntu 20.04. My trackpad isn't working properly. I have to press down somewhat to use the trackpad. That is the only time it works. How do I increase the sensitivity?

The Stunning Power of Questions

Much of an executive’s workday is spent asking others for information—requesting status updates from a team leader, for example, or questioning a counterpart in a tense negotiation. Yet unlike professionals such as litigators, journalists, and doctors, who are taught how to ask questions as an essential part of their training, few executives think of questioning as a skill that can be honed—or consider how their own answers to questions could make conversations more productive.

That’s a missed opportunity. Questioning is a uniquely powerful tool for unlocking value in organizations: It spurs learning and the exchange of ideas, it fuels innovation and performance improvement, it builds rapport and trust among team members. And it can mitigate business risk by uncovering unforeseen pitfalls and hazards.

For some people, questioning comes easily. Their natural inquisitiveness, emotional intelligence, and ability to read people put the ideal question on the tip of their tongue. But most of us don’t ask enough questions, nor do we pose our inquiries in an optimal way.

The good news is that by asking questions, we naturally improve our emotional intelligence, which in turn makes us better questioners—a virtuous cycle. In this article, we draw on insights from behavioral science research to explore how the way we frame questions and choose to answer our counterparts can influence the outcome of conversations. We offer guidance for choosing the best type, tone, sequence, and framing of questions and for deciding what and how much information to share to reap the most benefit from our interactions, not just for ourselves but for our organizations.