dmascc_cfg: 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/sbin/dmascc_cfg - from package: ax25-tools

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