cache_repair: 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 CentOS possible default full paths are:

/sbin/cache_repair - from package: device-mapper-persistent-data
/usr/sbin/cache_repair - from package: device-mapper-persistent-data

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/sbin/cache_repair - from package: thin-provisioning-tools

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

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