varnetload: 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:

/usr/sbin/varnetload - from package: tuned-utils

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

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