ldbash: 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/ldbash - from package: libbash

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

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