Monit

monit-alert-email

set alert [email protected]

set mailserver smtp.gmail.com port 587
    username "[email protected]"
    password "password"
    using TLSV1
    with timeout 30 seconds

set mail-format {
    from: [email protected]
    reply-to: [email protected]
    subject: [MONIT] $SERVICE $EVENT at $DATE
    message: Monit $ACTION $SERVICE at $DATE on $HOST: $DESCRIPTION.
             Yours sincerely,
             monit
}

monit-hdd-usage

check filesystem rootfs path /dev/xvda1
    if space usage > 80% for 5 times within 15 cycles then alert
    if space usage > 90% for 5 cycles then exec '/some/path/autoclean.sh'