vdlimit: 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 Debian possible default full paths are:

/usr/sbin/vdlimit - from package: util-vserver

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

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