brltty: 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:

/bin/brltty - from package: brltty

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

On Debian possible default full paths are:

/usr/lib/debug/sbin/brltty - from package: brltty-dbg
/sbin/brltty - from package: brltty

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

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