Installation/Linux/OpenFOAM-8/CentOS SL RHEL/6.10 (SCL)

For other versions of CentOS/RHEL/SL and other installation instructions, please visit the parent page: Installation/Linux/OpenFOAM-8/CentOS SL RHEL

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CentOS 6.10 (SCL)

Here you have the following choices:

You can install from source, by either:
- Following the official instructions from here: OpenFOAM Source Repository
- If you're looking for semi-automatic installation instructions, try Installation/Ansible.
- Or by following the detailed step-by-step instructions below...

Notes regarding the instructions below:

These instructions rely heavily on the Software Collections ( SCL ) Repository, which can be used to install software in a non-intrusive way... which will require its own environment loading mechanism.
- This way it's not necessary to compile Python and GCC from source code and instead use pre-built packages provided by the SCL community.
The instructions below were tested with CentOS 6.10, but might work with older or newer versions.

Discussion thread where you can ask questions about these steps: No thread available. Please a create a new thread in the forum.

Steps:

Switch to root mode (administrator), to install the necessary packages:
```
sudo -s
```
- If the 'sudo' command tells you're not in the sudoers list, then run:
```
su -
```

Install the necessary packages:

yum groupinstall 'Development Tools' 
yum install zlib-devel texinfo gstreamer-plugins-base-devel \
libXext-devel libGLU-devel libXt-devel libXrender-devel libXinerama-devel libpng-devel \
libXrandr-devel libXi-devel libXft-devel libjpeg-turbo-devel libXcursor-devel \
readline-devel ncurses-devel mpfr-devel gmp-devel
 
#This one is useful, but not crucial
yum upgrade

Also install the aforementioned SCL repository and the packages we need from it:

yum install centos-release-SCL
yum install python27 devtoolset-7

To check if the desired SCL packages are installed, run:
```
scl --list
```
For future reference, the easiest way to activate the environment for the installed SCL packages on the current command line is to run, but do not do this right now:
```
source /opt/rh/python27/enable
source /opt/rh/devtoolset-7/enable
```
This command will be indicated to be executed at the right point in the instructions below.
Now exit from the root mode:
```
exit
```
Start a new terminal. This is because you'll need a fully refreshed shell.

Download and unpack (here you can copy-paste all in single go):

#OpenFOAM downloading and installation
cd ~
mkdir OpenFOAM
cd OpenFOAM
git clone https://github.com/OpenFOAM/OpenFOAM-8.git
git clone https://github.com/OpenFOAM/ThirdParty-8.git

But we will now have to download a few more of the necessary packages for the ThirdParty-8 folder:

First, we need to prepare for the downloads:
```
cd ThirdParty-8
mkdir download
```

Now, we need to download the essential source code packages for these instructions you are following (the links are from the file README.org):

wget -P download  https://www.cmake.org/files/v3.9/cmake-3.9.0.tar.gz
wget -P download https://github.com/CGAL/cgal/releases/download/releases%2FCGAL-5.0.2/CGAL-5.0.2.tar.xz
wget -P download https://sourceforge.net/projects/boost/files/boost/1.72.0/boost_1_72_0.tar.bz2
wget -P download https://www.open-mpi.org/software/ompi/v2.1/downloads/openmpi-2.1.1.tar.bz2
wget -P download http://www.paraview.org/files/v5.6/ParaView-v5.6.3.tar.gz
wget -P download http://download.qt.io/archive/qt/5.9/5.9.6/single/qt-everywhere-opensource-src-5.9.6.tar.xz

Next, we need to unpack the packages we've downloaded:

tar -xzf download/cmake-3.9.0.tar.gz
tar -xJf download/CGAL-5.0.2.tar.xz
tar -xjf download/boost_1_72_0.tar.bz2
tar -xjf download/openmpi-2.1.1.tar.bz2
tar -xzf download/ParaView-v5.6.3.tar.gz --transform='s/ParaView-v5.6.3/ParaView-5.6.3/'
tar -xJf download/qt-everywhere-opensource-src-5.9.6.tar.xz --transform='s/qt-everywhere-opensource-src/qt-everywhere-src/'

Last but not least, the final command on this sub-list is to go back to the main OpenFOAM folder:
```
cd ..
```

A few details need to be fixed, before proceeding, which will change the default Boost and CGAL versions:

sed -i -e 's/\(boost_version=\)boost-system/\1boost_1_72_0/' OpenFOAM-8/etc/config.sh/CGAL
sed -i -e 's/\(cgal_version=\)cgal-system/\1CGAL-5.0.2/' OpenFOAM-8/etc/config.sh/CGAL

Now is the time to load in the SCL packages that were installed, by running:
```
source /opt/rh/python27/enable
source /opt/rh/devtoolset-7/enable
```
For building OpenFOAM itself, it depends on whether you have installed the i386 or x86_64 architecture of CentOS/SL/RHEL. To check this, run:
```
uname -m
```
Now, accordingly:
- For i386:
```
source $HOME/OpenFOAM/OpenFOAM-8/etc/bashrc WM_ARCH_OPTION=32 WM_MPLIB=OPENMPI FOAMY_HEX_MESH=yes
```
  Also, save an alias in the personal .bashrc file, simply by running the following command:
```
echo "alias of8='source /opt/rh/python27/enable && source /opt/rh/devtoolset-7/enable && source \$HOME/OpenFOAM/OpenFOAM-8/etc/bashrc $FOAM_SETTINGS'" >> $HOME/.bashrc
```
  Note: This last line means that whenever you start a new terminal window or tab, you should run the alias command associated to the OpenFOAM 8 shell environment. In other words, whenever you start a new terminal, you should run:
```
of8
```
  For more information on this topic, read section Using aliases to help manage multiple OpenFOAM versions in the page Installation/Working with the Shell.
- For x86_64, it depends on whether you need 64-bit integer support or not. Depending on whether you need 64-bit integer support or not:
  - For building with the normal 32-bit integer support (maximum 2.147×10⁹ cells, faces or points):
```
source $HOME/OpenFOAM/OpenFOAM-8/etc/bashrc WM_MPLIB=OPENMPI FOAMY_HEX_MESH=yes
```
  - For building with the normal 64-bit integer support (maximum 9.22×10¹⁸ cells, faces or points):
```
source $HOME/OpenFOAM/OpenFOAM-8/etc/bashrc WM_LABEL_SIZE=64 WM_MPLIB=OPENMPI FOAMY_HEX_MESH=yes
```
  Also, save an alias in the personal .bashrc file, simply by running the following command:
```
echo "alias of8='source /opt/rh/python27/enable && source /opt/rh/devtoolset-7/enable && source \$HOME/OpenFOAM/OpenFOAM-8/etc/bashrc $FOAM_SETTINGS'" >> $HOME/.bashrc
```
  Note: This last line means that whenever you start a new terminal window or tab, you should run the alias command associated to the OpenFOAM 8 shell environment. In other words, whenever you start a new terminal, you should run:
```
of8
```
  For more information on this topic, read section Using aliases to help manage multiple OpenFOAM versions in the page Installation/Working with the Shell.
CentOS 6.10 comes with CMake 2.6.4, but ParaView 5.6.3 needs a one of the versions from the more recent CMake 3.x series, so we need a custom build:
```
cd $WM_THIRD_PARTY_DIR
./makeCmake > log.makeCmake 2>&1
wmRefresh
```
CentOS 6.6 comes with Qt 4.6.2, but ParaView 5.6.3 needs at least 5.X. However, since we are using GCC 7, it's best to use a more recent Qt version, namely 5.9.6 was downloaded and unpacked already. Therefore, we'll need to do a custom build of Qt 5.9.6:
```
cd $WM_THIRD_PARTY_DIR
 
#Get the scripts we need
wget https://github.com/wyldckat/scripts4OpenFOAM3rdParty/raw/master/makeQt5
wget -P etc/tools/ https://github.com/OpenFOAM/ThirdParty-2.4.x/raw/master/etc/tools/QtFunctions
 
#make them executable
chmod +x makeQt5
 
./makeQt5 qt-5.9.6 > log.makeQt 2>&1
```
Important Note: Building Qt 5 will use up a lot of disk space (roughly 10GB, including the source code package). Therefore, after you've check the contents of the file log.makeQt (or check the last few lines of this file), then you can delete the temporary+intermediate files used to build Qt 5, by running the following commands:
```
cd $WM_THIRD_PARTY_DIR
rm -r build
rm -r qt-everywhere-src-5.9.6
```
Given that a custom Open-MPI version is being built with these instructions, it's necessary to first build it before ParaView so that Open-MPI can be used by ParaView:
```
cd $WM_THIRD_PARTY_DIR
./Allwmake > log.make 2>&1
wmRefresh
```

For building ParaView 5.6.3 with Python and MPI, it depends on whether you have installed the i686 or x86_64 architecture of CentOS 6:

To check this, run:

uname -m

Now, accordingly:

For i686:

cd $WM_THIRD_PARTY_DIR
 
# Load the Python 2.7 that came with the SCL repository
source /opt/rh/python27/enable
 
# Need Qt5 to be found by CMake
export CMAKE_PREFIX_PATH=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/qt-5.9.6/
 
#this will take a while... somewhere between 30 minutes to 2 hours or more
./makeParaView -qt-5.9.6 -mpi -python -python-lib /opt/rh/python27/root/usr/lib/libpython2.7.so -python-include /opt/rh/python27/root/usr/include/python2.7 > log.makePV 2>&1

For x86_64:

cd $WM_THIRD_PARTY_DIR
 
# Load the Python 2.7 that came with the SCL repository
source /opt/rh/python27/enable
 
# Need Qt5 to be found by CMake
export CMAKE_PREFIX_PATH=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/qt-5.9.6/
 
#this will take a while... somewhere between 30 minutes to 2 hours or more
./makeParaView -qt-5.9.6 -mpi -python -python-lib /opt/rh/python27/root/usr/lib64/libpython2.7.so -python-include /opt/rh/python27/root/usr/include/python2.7 > log.makePV 2>&1

Note: Building with Qt 5 means that OpenGL2 must be used, therefore if you really want to use OpenGL rendering, follow the instructions from section CentOS 6.10 (without SCL) instead.

Once the makeParaView script is finished running, make sure to check the contents of the file log.makePV and check if there are any errors. If you have any problems building or using ParaView, please check the ParaView installation FAQ page.
Finally, update the shell environment:
```
wmRefresh
```

Now let's build OpenFOAM:
1. Go into OpenFOAM's main source folder:
```
cd $WM_PROJECT_DIR
```
2. We need to temporarily populate CMAKE_PREFIX_PATH with the path to the custom Qt build, so that qmake is properly found when building OpenFOAM's plug-in libraries for ParaView:
```
export CMAKE_PREFIX_PATH=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/qt-5.9.6/
```
3. This next command will take a while... somewhere between 30 minutes to 3-6 hours:
```
./Allwmake -j 4 > log.make 2>&1
```
  Note: The "4" refers to the number of cores to be used for building in parallel. In addition, the amount of RAM needed for building scales with the number of cores used, something like 1GB of RAM per core; a minimum of 1.5GB is needed for linking the libraries, which is not done in parallel.
4. Run it a second time for getting a summary of the installation:
```
./Allwmake -j 4 > log.make 2>&1
```
  Note: Technically, the build will stop as soon as the first error is found. Running a second time only makes it easier to sort through between what's already been built and where the crash occurred.
To check if everything went well:
1. Check if icoFoam is working, by running this command:
```
icoFoam -help
```
  which should tell you something like this:
```
Usage: icoFoam [OPTIONS]
options:
  -case <dir>       specify alternate case directory, default is the cwd
  -noFunctionObjects
                    do not execute functionObjects
  -parallel         run in parallel
  -roots <(dir1 .. dirN)>
                    slave root directories for distributed running
  -srcDoc           display source code in browser
  -doc              display application documentation in browser
  -help             print the usage
```
  Note: And keep in mind that you need to be careful with the letter case of the command. It's icoFoam, not icoFOAM.
2. If the previous command failed to work properly, then edit the file log.make and check if there are any error messages. A few examples on how you can edit this file:
  - By using kwrite:
```
kwrite log.make
```
  - By using gedit:
```
gedit log.make
```
  - By using nano:
```
nano log.make
```
    You can then exit by using the key combination Ctrl+X and following any instructions it gives you.
  Note: It's the first error message that matters.
3. If you don't understand the output, then please compress the log-file log.make and attach the compressed file to a post in the designated thread.
  If you do not know how to create a compressed file, then try one of the following examples:
  - You can compress the file with gzip by running this command:
```
gzip < log.make > log.make.gz
```
    Then attach the resulting package file named log.make.gz to a post in the designated thread.
  - Or you can compress one or more log-files into a tarball package file, by running this command:
```
tar -czf logs.tar.gz log.*
```
    Then attach the resulting package file named logs.tar.gz to a post in the designated thread.
4. Instructions on how to further diagnose the issue yourself, have a look at the section Common errors when building OpenFOAM from source code in the page FAQ/Installation and Running.
Now you can go read the User Guide, where you may have more than one choice:
1. Which you can find a local copy of the User Guide by running the following command:
```
ls -A1 $WM_PROJECT_DIR/doc/Guides*/*UserGuide*.pdf
```
  - You should see two available formats: A4 and US-Letter.
  - But if it instead tells you that there is No such file or directory, then the OpenFOAM environment is possibly not properly activated.
2. You can also find the more recent OpenFOAM Foundation User Guides online at the following page: official OpenFOAM User Guide - but be careful if you use the version that is too much ahead of the version you are currently using, given that some features have changed overtime.
Note: When you want to update your build, follow the instructions on section Steps for updating on the parent page.

Reminder: Whenever you start a new terminal window or tab, you should run the alias command associated to the OpenFOAM 8 shell environment. In other words, run the following command whenever you start a new terminal:

of8

For more information on this topic, read section Using aliases to help manage multiple OpenFOAM versions in the page Installation/Working with the Shell.

Discussion thread where you can ask questions about these steps: No thread available. Please a create a new thread in the forum.