bip: 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/bip - from package: bip

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

On Debian possible default full paths are:

/usr/bin/bip - from package: bip

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

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