crossystem: 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/crossystem - from package: vboot-utils

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

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