qslog: command not found

Have You tried accessing the binary with the full path?

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/qslog - from package: libapache2-mod-qos

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