birdc: 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/sbin/birdc - from package: bird

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

On Debian possible default full paths are:

/usr/sbin/birdc - from package: bird-bgp
/usr/sbin/birdc - from package: bird

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