pcs: 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
/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/sbin/pcs - from package: pcs

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