distccmon-gnome: 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 CentOS possible default full paths are:

/usr/bin/distccmon-gnome - from package: distcc

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

On Debian possible default full paths are:

/usr/bin/distccmon-gnome - from package: distccmon-gnome

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