collectdmon: 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/sbin/collectdmon - from package: collectd

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

On Debian possible default full paths are:

/usr/sbin/collectdmon - from package: collectd-core
/usr/lib/debug/usr/sbin/collectdmon - from package: collectd-dbg

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

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