inotifywait: 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/inotifywait - from package: inotify-tools

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

On Debian possible default full paths are:

/usr/bin/inotifywait - from package: inotify-tools

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

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