flog: 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/flog - from package: flog

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

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