avisd: 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/sbin/avisd - from package: avis

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

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