varnishsizes: 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/bin/varnishsizes - from package: varnish

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

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