cdpinger: 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/sbin/cdpinger - from package: ltspfsd

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