traffic_crashlog: 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/traffic_crashlog - from package: trafficserver

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