flashcache_setioctl: 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

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/flashcache_setioctl - from package: flashcache-utils

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