dpm-rmpool: 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/dpm-rmpool - from package: dpm

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

On Debian possible default full paths are:

/usr/bin/dpm-rmpool - from package: dpm

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