zrancid: 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 Debian possible default full paths are:

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

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

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