vgcfgbackup: 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/vgcfgbackup - from package: lvm2

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

On Debian possible default full paths are:

/sbin/vgcfgbackup - from package: lvm2

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

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