nfs_cache_getent: 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/nfs_cache_getent - from package: nfs-utils

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

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