arm-none-eabi-g++: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/arm-none-eabi-g++ - from package: gcc-arm-none-eabi

You may install the required package with command apt-get install {package}
Error in other languages:
arm-none-eabi-g++: bevel nie gevind nie
arm-none-eabi-g++: comandă negăsită
arm-none-eabi-g++: comando não encontrado
arm-none-eabi-g++: commande introuvable
arm-none-eabi-g++: command not found
arm-none-eabi-g++: käsku ei ole
arm-none-eabi-g++: không tìm thấy lệnh
arm-none-eabi-g++: komanda nerasta
arm-none-eabi-g++: Kommando nicht gefunden.
arm-none-eabi-g++: kommandot finns inte
arm-none-eabi-g++: komut yok
arm-none-eabi-g++: nie znaleziono polecenia
arm-none-eabi-g++: níor aimsíodh an t-ordú
arm-none-eabi-g++: no se encontró la orden
arm-none-eabi-g++: no s'ha trobat l'ordre
arm-none-eabi-g++: opdracht niet gevonden
arm-none-eabi-g++: parancs nem található
arm-none-eabi-g++: perintah tidak ditemukan
arm-none-eabi-g++: príkaz nenájdený
arm-none-eabi-g++: příkaz nenalezen
arm-none-eabi-g++: команда не найдена
arm-none-eabi-g++: командата не е открита
arm-none-eabi-g++: 命令找不到
arm-none-eabi-g++: コマンドが見つかりません