ipvsadm: 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/ipvsadm - from package: ipvsadm

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

On Debian possible default full paths are:

/sbin/ipvsadm - from package: ipvsadm

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

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