Tag Archives: ubuntu

[Solved] Login with Ubuntu graphical interface, error sorry, that didn’t work.please try again

Sorry, that didn’t work.please try again

Today, I just finished installing Ubuntu 20.04. After setting the root password, I found that the root login would report such an error:
sorry, that didn’t work.please try again

In fact, there is no problem with the command line login, which indicates that it is not the password, but the desktop environment.

vi /etc/pam.d/gdm-autologin
#Note "auth requied pam_succeed_if.so user != root quiet success"

vi /etc/pam.d/gdm-password
#Note "auth requied pam_succeed_if.so user != root quiet success"

Unbuntu 18.04 unable to install mkcramfs

Problem description

In the morning, I received user feedback and applied to add mkcramfs and libxml dev to the offline source
which was strange. After asking the user, the user gave a screenshot of the question:

Problem analysis

Firstly, the first step is to get the user node information and login mode, and the path of the command in the screenshot
after logging in, the user problem is reproduced, and the error is indeed reported; Try the following:

1、apt-get install mkcramfs

Report an error, indicating that there is no such package

2、apt-get install libxml2-dev

I still report an error. I feel strange. I suspect that there is something wrong with the source.
3. Check the source configuration of the user’s machine and find that there is no/etc/apt/source.list file, only/etc/apt/source.text; The reason is that the MV of the last step is not executed when the user installs the offline source document.
4. Modify the source information and update it

mv /etc/apt/source.text /etc/apt/source.list
apt-get update

5. After trying to install the previous two packages, it is found that libxml2 dev is installed normally, and mkcramfs cannot be installed

Problem solving

For all the relevant information on the Internet, it is found that some Ubuntu can’t install mkcramfs in APT get mode, so they need to download the package to the local and then install it.
1. Find the corresponding package in the offline source, and then download it:

2. Install it in dpkg-i mode
3. Verify it by performing the user’s previous operation; Problem solving:

Summary

Some Ubuntu can’t install mkcramfs in APT get mode, so you need to download the package to the local and then install it
extension: there may be other packages with this situation, which can be used as a reference for subsequent analysis

About LCM spy running error in LCM v1.4.0

I am a little white, but recently in the Linux system running LCM spy encountered a variety of error messages. Finally, after collecting all kinds of information on the Internet and a little bit of my imagination, I successfully solved the problem, so I want to share it with you and leave a file for myself, so as not to be at a loss when I encounter the same problem in the future.

First, follow the official LCM guidelines   Before installing LCM, be sure to download its recommended default JDK. This automatic download is the latest version of Java (I don’t know much about Java, but it also seems to download javac). Bloggers download Java 11 by default. Note: Java 8 can’t run make successfully, at least the blogger failed.

Default JDK installation steps:

$ sudo apt update
$ sudo apt install default-jdk

Then follow the steps to install according to the official website (cmake may say that some files in other languages cannot be found, but you can try to run make first)

$ mkdir build
$ cd build
$ cmake ..
$ make
$ sudo make install

If there is no error in make and make install, please check whether there is an LCM Java folder and whether there is lcm.jar in the folder under build. This is very important, because it determines whether you can run LCM spy

Next, you need to download Java 8 and change the default version of Java to Java 8. The method is as follows (the first and second behaviors download Java 8, and the third behavior change the version)

$ sudo apt-get update
$ sudo apt-get install openjdk-8-jdk
$ sudo update-alternatives --config java

Then select the number corresponding to Java 8 in the pop-up window and press enter:

Next, you need to move the lcm.jar to the Java folder. Note: the specific address varies from person to person. Please check the address of the Java folder in usr. Bloggers provide their own examples:

$ sudo cp ~/lcm-1.4.0/build/lcm-java/lcm.jar /usr/share/java/

In this way, you can find the LCM. Jar file in the Java folder. If there is no accident, you can run LCM spy and LCM logplayer GUI in any path.

——————————————————————————————————————————

PS:

1. Two versions of Java are needed because during the installation of LCM v1.4.0, Java related files only support Java 11 (maybe Java 10), but not Java 8. However, the operation of LCM spy does not support Java 11, because Java 11 has deleted an option named “xincgc” in Java 8, so it needs to change the Java version to Java 8 to run successfully;

2. A Java application notes in the official website   Bloggers did not run successfully, so they have to manually copy LCM. Jar to the Java folder. If you are interested, you can also try whether the official website tutorial is useful.

linux Ubuntu Error: No command ‘setenv‘ found

 

Linux Ubuntu error: no command ‘setenv’ found

 

Foreword solution


preface

   sometimes the installed software commands are written based on CSH. If you use bash to use the software, you will report an error, such as “no command ‘setenv’ found”. At this time, you need to change the default bash of Ubuntu to CSH

resolvent

   Linux Ubuntu changes the default bash to CSH by default

How to Solve Error: “Hdaudio hdaudioc0d2: unable to bind codec”

recently, after installing nidia drivers on the platform of Ubuntu 18.04, restart the computer, report the error “hdaudio hdaudioc0d2: unable to bind codec” on the command line, and the startup interface stays in the shell interface</ font>

note: there are many solutions to this problem on the Internet, but they don’t talk about the permission problem. The pro test can only save the modified grub file under the permission of root

resolvent

1. Enter super user root:

sudo -i

2. Enter grub file:

vim /etc/default/grub

3. Modify the following contents: before modification: </ font> </ font> 1

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"

Modify:

GRUB_CMDLINE_LINUX_DEFAULT=""

4. Save the file: </ font> </ font>

ESC +:x

U-boot NFS download file error: loading: * * * error: File lookup fail solution

The reason for this error is:
the version of NFS used in uboot is V2, while the version of NFS used in Ubuntu is V3, V4 and above. As a result, uboot can no longer find files in the NFS server.

The solution is to make NFS in buntu compatible with v2. Modify the /etc/default/NFS kernel server file.

Open the file: sudo VIM/etc/default/NFS kernel server (note that sudo or root permissions are required), and modify it as follows:

# Number of servers to start up
RPCNFSDCOUNT=" -V 2 8"

# Runtime priority of server (see nice(1))
RPCNFSDPRIORITY=0

# Options for rpc.mountd.
# If you have a port-based firewall, you might want to set up
# a fixed port here using the --port option. For more information, 
# see rpc.mountd(8) or http://wiki.debian.org/SecuringNFS
# To disable NFSv4 on the server, specify '--no-nfs-version 4' here
RPCMOUNTDOPTS="-V 2 --manage-gids"

# Do you want to start the svcgssd daemon?It is only required for Kerberos
# exports. Valid alternatives are "yes" and "no"; the default is "no".
NEED_SVCGSSD=""

# Options for rpc.svcgssd.
RPCSVCGSSDOPTS="--nfs-version 2,3,4 --debug --syslog"

Restart the NFS server. sudo service nfs-kernel-server restart

How to Solve Error “ImportError: cannot import name imsave“

Problem description

Today, when running a GitHub code two years ago, an error was reported:

from scipy.misc import imsave

ImportError: cannot import name 'imsave'

But after checking, I found that I have installed the SciPy module. When checking the internal function module of SciPy, I found that there are no functions such as imsave

import scipy.misc

print(dir(scipy.misc))

After searching, it is found that the reason is the SciPy version: after SciPy 1.3, functions such as SciPy. Misc. Imread/imsave will be discarded.

resolvent

To re install the previous version of SciPy, first log in to the official website of SciPy and find the corresponding WHL file. As the python environment of this machine is Ubuntu + python = 3.6.9, download the third corresponding file:

Then uninstall the previous SciPy and install the file

# uninstal scipy
pip uninstall scipy


# install
pip install scipy-1.2.0-cp36-cp36m-manylinux1_x86_64.whl

Check the SciPy internal function again

 

You can see that there are functions like imread, imsave, imshow, etc

Linux Ubuntu ImportError: Libtk8.5.so: cannot open shared object file:No such file Install tkinter Library

Ubuntu resolves errors importerror: libtk8.5.so: cannot open shared object file:No such File to install Tkinter Library

 

terms of settlement


terms of settlement


at the beginning, I wanted to install with PIP3, but all of them made mistakes. It seems that PIP does not have this library?Then use </ font> instead

sudo apt-get update
sudo apt-get install python3-tk

   done

note: if there is an error in the installation process, you can refer to my previous article to add image source processing – Linux Ubuntu modify image source

 

The solution of unsuccessful rosdep update

After encountering this problem, we refer to no less than ten online tutorials, none of which is effective, including but not limited to:

1. Hang up VPN (it seems that many people finally rely on science to get online, but I still can’t hang it here

2. Modify the upper limit of time parameter: useless, the system has the default maximum value, about one minute, to treat the symptoms but not the root cause

3. Modify the host file: all kinds of addresses of Google and GitHub have been added in, which is useless

4. Hang hot spot: same as 1, useless

For the final solution, please refer to Baidu Post Bar:

sudo apt-get update

sudo apt-get install python-rosdep

  In the second step, there is an error message when installing Python rosdep. It seems that some files were not successfully installed, but in the end, rosdep update succeeded.

Create a new project in pycharm: modulenotfounde rror:No module named ‘distutils.util‘

The error is as follows:

Don’t panic. It’s not a big problem

When installing pycharm in the Ubuntu system and creating a new project, prompt

ModuleNotFoundError: No module named ‘distutils.util’

The reason is that Ubuntu 18.04 does not install PIP by default, so you need to install python3 pip,

Enter the command in the terminal:

sudo apt-get install python3-pip

When you create a new project again, the problem can be solved

The resolution of Ubuntu 16.04 screen can’t be modified and the solution of circulating login

Today, there are many problems with the graphics card driver. One of them is that after the computer restarts, the resolution of the display screen becomes 800600, and the normal resolution is 19201080. There is no other resolution option in the system settings, so it cannot be modified. Try to create the xorg. Conf file, which is described on the Internet, to set the custom desktop resolution. After the modification, the resolution has changed, but it is 1600 * 1200, which is still very abnormal. Using the combination of CVT and xrandr to modify the resolution indicates another error, xrandr: failed to get size of gamma for output default. One problem after another, what a tangle!

It has to be said that it’s really unpleasant to search these professional problems with Baidu in China. What often appears are some irrelevant or unsolvable web pages. Fortunately, it’s all solved now, and the problem is still in the driver side of the graphics card [1]. Software & amp; update in system settings; In updates, click additional drivers and change it to NVIDIA driver (I choose the third one here, as shown in the figure below). The application modification needs to wait for a little time, restart the computer after completion, and the resolution is normal again.

After the driver is re installed, the problem of circular login appears again. You may encounter it later. Record the solution here.

ctrl +alt +f2  
sudo service lightdm stop  
sudo apt-get --purge remove nvidia-*  

After many months, I stepped on the big pit of circular login again, but the previous solution was invalid. Another possible problem is that the owner and all groups of the. Xauthority file become root. There is a. Xauthority file in the user’s home directory. View the owner and all groups of the file

ls -la .Xauthority

If it is root, you need to change it to your login user:

sudo chown username:username .Xauthority

(there will always be all kinds of accidents in the actual solution, one by one, don’t worry.)