getpeername: 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/getpeername - from package: tcputils

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

On Debian possible default full paths are:

/usr/bin/getpeername - from package: tcputils

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

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