dsh: 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/dsh - from package: dsh

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

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