lnst-slave: 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/lnst-slave - from package: lnst-slave

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

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