pcp-lvmcache: 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:

/usr/libexec/pcp/bin/pcp-lvmcache - from package: pcp

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

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