dnstracer: 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/bin/dnstracer - from package: dnstracer

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

On Debian possible default full paths are:

/usr/bin/dnstracer - from package: dnstracer

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

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