planner: 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/planner - from package: planner

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

On Debian possible default full paths are:

/usr/bin/planner - from package: planner

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

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