nfs4_setfacl: 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/bin/nfs4_setfacl - from package: nfs4-acl-tools

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

On Debian possible default full paths are:

/usr/bin/nfs4_setfacl - from package: nfs4-acl-tools

You may install the required package with command apt-get install {package}
Error in other languages:
nfs4_setfacl: bevel nie gevind nie
nfs4_setfacl: comandă negăsită
nfs4_setfacl: comando não encontrado
nfs4_setfacl: commande introuvable
nfs4_setfacl: command not found
nfs4_setfacl: käsku ei ole
nfs4_setfacl: không tìm thấy lệnh
nfs4_setfacl: komanda nerasta
nfs4_setfacl: Kommando nicht gefunden.
nfs4_setfacl: kommandot finns inte
nfs4_setfacl: komut yok
nfs4_setfacl: nie znaleziono polecenia
nfs4_setfacl: níor aimsíodh an t-ordú
nfs4_setfacl: no se encontró la orden
nfs4_setfacl: no s'ha trobat l'ordre
nfs4_setfacl: opdracht niet gevonden
nfs4_setfacl: parancs nem található
nfs4_setfacl: perintah tidak ditemukan
nfs4_setfacl: príkaz nenájdený
nfs4_setfacl: příkaz nenalezen
nfs4_setfacl: команда не найдена
nfs4_setfacl: командата не е открита
nfs4_setfacl: 命令找不到
nfs4_setfacl: コマンドが見つかりません