ii: command not found

Have You tried accessing the binary with the full path?

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/ii - from package: ii

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