get_agsize: 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:

/sbin/get_agsize - from package: flashcache-utils

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

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