Add your user to the group - CentOS 7 & Virtual Box

 sudo usermod -G vboxsf -a myusername

How to Configure Internet access on a CentOS Minimal install

May

By default a CentOS minimal install can't connect to the network or the internet, in order to configure it to access the outside world you need to follow the following steps:

1. Configure the DHCP client on the default network interface eth0 by executing the following command:

dhclient eth0

2. Edit the main network configuration file to make sure networking is enabled using the command

vi /etc/sysconfig/network

and make sure that it has networking set to yes

NETWORKING=yes

3. Edit the network configuration file for eth0 to enable it to use a dynamic ip using dhcp

vi /etc/sysconfig/network-scripts/ifcfg-eth0

4. Modify the file to have the following

DEVICE="eth0"
BOOTPROTO="dhcp"
ONBOOT="yes"
NM_CONTROLLED="no"

4. Save the file and then restart the network service using the following command

service network restart

5. Make sure that eh0 has pulled an IP using the following command

ifconfig

Tun Ubuntu 18.04 in Enhanced Mode in Hyper-V

Hyper-V

Install ubuntu in generation 2 mode
Un-check secure boot

Ubuntu OS

#Get the scripts from GitHub
$ sudo apt-get update
$ sudo apt install git
$ git clone https://github.com/jterry75/xrdp-init.git ~/xrdp-init

#Make the scripts executable and run them...
$ cd ~/xrdp-init/ubuntu/18.04/

$ sudo chmod +x install.sh
$ sudo ./install.sh
$ reboot

Windows powershell in administratoe mode:

Set-VM -VMName Ubuntu -EnhancedSessionTransportType HvSocket

Log-in

UNCHECK Printers in local resources.

Unable to start the geometry editor ANSYS WB on CENTOS

export LD_LIBRARY_PATH=/usr/ansys_inc/v172/Framework/bin/Linux64/Mesa

sudo nano ~/.bashrc

export LD_LIBRARY_PATH=/usr/ansys_inc/v180/Framework/bin/Linux64/Mesa

Virtualbox shared folder permissions

Solution 1

Edit the file /etc/group. Look for the line vboxsf:x:999 and add at the end :yourusername

Solution 2

Run sudo adduser yourusername vboxsf

Fluent 17.2 C++compiler

For the case if you have troubles with C++ compiler and tools installation and some bugs, the following workaround will help you.

1) Download and install Microsoft Visual studio, say 2015.
2) Browse to C:\Program Files\ANSYS Inc\v172\fluent\ntbin\win64 and backup udf.bat to udf.bat.ORIG
3) Place the following code to udf.bat

@echo off
rem ---
rem MS Visual C++
rem ---
set MSVC=
set MSVC_VERSION=0

set MSVC_VERSION=172
call "c:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Auxiliary\Build\vcvarsall.bat" x86_amd64

echo Detected MSVC%MSVC_VERSION% under ""
echo path=%path%
echo include=%include%
echo lib=%lib%


4) Make sue that in Fluent launcher on the Environment Tab the the Set up Compilation Environment for UDF checkbox is picked up.

Enjoy...

Also useful information can be found here -   COMPILING AND LOADING USER DEFINED FUNCTIONS USING FLUENT 14.5 OR 15.0

Linux cached memory

https://www.linuxatemyram.com

https://www.linuxatemyram.com/play.html

mpurun error 19 more processes have sent help message help-mpi-btl-base.txt / btl:no-nics Set MCA parameter "orte_base_help_aggregate" to 0 to see all help / error messages

If you get mpurun error as 

N more processes have sent help message help-mpi-btl-base.txt / btl:no-nics

Set MCA parameter "orte_base_help_aggregate" to 0 to see all help / error messages

the workaround is to add to the command

--mca btl ^openib

to disable the openib btl

Remove Docker Images & Containers

docker stop $(docker ps -a -q)

docker ps -a
docker rm  <CONTAINER ID>

docker images
docker rmi  <IMAGE ID>

Adobe Acrobat in Ubuntu 16.04

sudo add-apt-repository "deb http://archive.canonical.com/ precise partner"
sudo apt-get update
sudo apt install adobereader-enu

sudo add-apt-repository -r "deb http://archive.canonical.com/ precise partner"

comsol /dev/null &

comsol server </dev/null > /dev/null &