tcpcapinfo: 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/tcpcapinfo - from package: tcpreplay

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

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