vgrename: 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/vgrename - from package: lvm2

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

On Debian possible default full paths are:

/sbin/vgrename - from package: lvm2

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

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