Cortex

Cortex is a computation rack for VisLab humanoid robots.

The Cluster

It contains 7 machines:

• 1 server that manages startup, shutdown and the file system of the clients.
• 6 clients that run the user processes.

All clients mount the same file system. Therefore, performing changes in the file system of one of the clients will reflect to all others.

The Network

Cortex machines are at the vislab robotics network domain:

• Domain: visnet
• Subnet: 10.10.1.*

Cortex nodes

Cortex server and clients have the following ip's and domain names:

• Server: 10.10.1.240, server.visnet
• Client 1: 10.10.1.1, cortex1.visnet
• Client 2: 10.10.1.2, cortex2.visnet
• Client 3: 10.10.1.3, cortex3.visnet
• Client 4: 10.10.1.4, cortex4.visnet
• Client 5: 10.10.1.5, cortex5.visnet
• Client 6: 10.10.1.6, cortex6.visnet

Other nodes

Other assigned ip's and names are:

• Gateway: 10.10.1.254, gtisr.visnet
• Cortex Switch: 10.10.1.250, swcompurack.visnet
• Vislab Switch: 10.10.1.251, swvislab.visnet
• iCubBrain1: 10.10.1.41, icubbrain1.visnet
• iCubBrain2: 10.10.1.42, icubbrain2.visnet
• DHCP Range: 10.10.1.100-199
• Chico Net: 10.10.1.50-59
• Chica Net: 10.10.1.60-69
• Balta Net: 10.10.1.70-79

DNS Configuration

Name resolution in the visnet network is managed by a bind system in server.visnet. To add/change the table of names and ip's do 'cd /etc/bind', edit and change the file ' /visnet.src' (need super user permission)and then run 'make'.

Connectivity

Cortex machines are connected to Cortex Switch, that links to Vislab switch with a fiber optic connection of 4Gb/s.

Traffic

Network traffic can be checked at:

• http://inode1.isrnet/cacti (user guest, pass guest)

The Cortex Server

The server has:

• Boot folder for the clients at /tftpboot/pxelinux.cfg. Contains the files:
  • default - default boot file
  • <mac_address> - specific for a machine with the given mac address.
• startup scripts for each machine at /nfsroot/app

The Cortex Clients

Configuration

The clients have:

• A superuser account (compurack) to administer system wide settings (configurations, libs, etc)
• Normal user accounts. The logon script runs by default the content of file $HOME/.bash_env, where users can set their environment variables, e.g. export ICUB_DIR=$HOME/iCub.
• A yarp account to update and install the yarp library. YARP_DIR is set by default to /home/yarp/yarp2 to all users (in /etc/bash.bashrc).
• An "icub" account with sudo privileges (done with sudo adduser icub admin on 2009-06-30)

Global Libraries and Repositories

YARP

Yarp was set using the following commands (after logging in as yarp):

  cvs -d:pserver:anonymous@yarp0.cvs.sourceforge.net:/cvsroot/yarp0 login
  cvs -z3 -d:pserver:anonymous@yarp0.cvs.sourceforge.net:/cvsroot/yarp0 co -P yarp2
  cd yarp2
  cmake .    (or ccmake .)
  make
  make test

OTHER

Other system wide libraries/apps are installed by the superuser. Currently the following libraries are installed:

CURSES

  apt-get install libncurses5-dev

ACE

  apt-get install libace-dev

CMAKE

  apt-get install cmake

GSL

  apt-get install libgsl0-dev

GTK/GTKMM/GLADE

  apt-get install libgtk2.0-dev
  apt-get install libgtkmm-2.4-dev
  apt-get install libglademm-2.4-dev

OPENCV

  THE REPOSITORY IS NOW IN SVN FORM, WE NEED TO UPDATE THIS.
  cvs -z3 -d:pserver:anonymous@opencvlibrary.cvs.sourceforge.net:/cvsroot/opencvlibrary co -P opencv
  cd opencv
  ./configure
  make
  make install
  add /usr/local/lib to /etc/ld.so.conf

GLEW (OpenGL extension finder)

 apt-get install glew-utils
 apt-get install libglew1.5-dev

GLUT (Glu Utility toolkit)

apt-get install libglut-dev

User Repositories

Each user should manage its own repositories, e.g. the iCub repository:

  cvs -d vislab@cvs.robotcub.org:/cvsroot/robotcub co iCub

then you should add <iCub>/bin to your PATH by editing your ~/.bashrc like this:

 PATH=$PATH:~/iCub/bin/
 ICUB_DIR=~/iCub/
 export ICUB_DIR
 ICUB_ROOT=$ICUB_DIR
 export ICUB_ROOT

You should also edit ~/.bash_env adding these lines:

 export ICUB_DIR=$HOME/iCub
 export ICUB_ROOT=$ICUB_DIR

this is needed when you connect non-interactively via ssh to a Cortex computer, for instance when execute a "yarp run ..." on a Cortex, from Chico2.

Be aware that Ubuntu 7.10 (the version currently installed on the cluster) has a conflict with iKin, specifically with iCub/conf/FindIPOPT.cmake (used by iKin): for now, in order to compile iKin, change the following line of FindIPOPT.cmake from

  SET(IPOPT_LIB   ${IPOPT_LIB} gfortranbegin gfortran)

to

  SET(IPOPT_LIB   ${IPOPT_LIB} gfortran)

Other configurations

Network tuning

  sysctl -w net.core.rmem_max=8388608
  sysctl -w net.core.wmem_max=8388608
  sysctl -w net.core.rmem_default=65536
  sysctl -w net.core.wmem_default=65536
  sysctl -w net.ipv4.tcp_rmem='4096 87380 8388608'
  sysctl -w net.ipv4.tcp_wmem='4096 65536 8388608'
  sysctl -w net.ipv4.tcp_mem='8388608 8388608 8388608'
  sysctl -w net.ipv4.route.flush=1

Prompt ($PS1)

The prompt is set to "user@cortex?:pwd$" in /etc/bash.bashrc. With those settings, if you log in to Cortex1, the prompt will be "user@cortex1:~$". We chose to do so because sometimes it's convenient to have the number of the Cortex machine you're working on embedded in the prompt. By default, though, this configuration is overridden in the users' ~/.bashrc file, and the prompt is set to "user@source" regardless of the Cortex machine you log in to.
If you want to inhibit this behaviour in ~/.bashrc and thus have a prompt like "user@cortex?:pwd", just comment these lines in your ~/.bashrc:

  # set a fancy prompt (non-color, unless we know we "want" color)
  case "$TERM" in
  xterm-color)
      PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
      ;;
  *)
      PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
      ;;
  esac

However, for users created after 2009-05-07, the prompt is already set to "user@cortex?:pwd$" by default.

Helper commands

• Check the kernel : uname -m

• Check the file versions : file

• Set bash shell in /etc/passwd

• Check disk space: du –h –s /home

• Check per user processes: ps -U <user>