agmrancid: 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 Debian possible default full paths are:

/usr/lib/rancid/bin/agmrancid - from package: rancid

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