otter: 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 Debian possible default full paths are:

/usr/bin/otter - from package: otter

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

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