cdfvertmean: 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/bin/cdfvertmean - from package: cdftools

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

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