doctrine: command not found

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 CentOS possible default full paths are:

/usr/bin/doctrine - from package: php-doctrine-orm

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/doctrine - from package: php-doctrine-orm

You may install the required package with command apt-get install {package}

Error in other languages:
doctrine: bevel nie gevind nie
doctrine: comandă negăsită
doctrine: comando não encontrado
doctrine: commande introuvable
doctrine: command not found
doctrine: käsku ei ole
doctrine: không tìm thấy lệnh
doctrine: komanda nerasta
doctrine: Kommando nicht gefunden.
doctrine: kommandot finns inte
doctrine: komut yok
doctrine: nie znaleziono polecenia
doctrine: níor aimsíodh an t-ordú
doctrine: no se encontró la orden
doctrine: no s'ha trobat l'ordre
doctrine: opdracht niet gevonden
doctrine: parancs nem található
doctrine: perintah tidak ditemukan
doctrine: príkaz nenájdený
doctrine: příkaz nenalezen
doctrine: команда не найдена
doctrine: командата не е открита
doctrine: 命令找不到
doctrine: コマンドが見つかりません