dvdisaster: 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/dvdisaster - from package: dvdisaster

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

On Debian possible default full paths are:

/usr/bin/dvdisaster - from package: dvdisaster

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

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