Symmetricom released the latest firmware with a
feature to turn off/disable the ntp query.
Here are the steps to upgrade the firmware:
1. Log in to Web GUI. Go to SYSTEM > Upgrade page.
2. Click BROWSE... button to select the firmware. Then
click UPLOAD button.
3. Click the firmware inside Current Files window. Then
click INSTALL button.
4. Log into CLI via SSH after
the upgrade.
5. Type “ntp_query” and press Enter. This should show
“Queries are not restricted and will be responded to”
6. Type “ntp_query disable” and press Enter. Type “Y” to
confirm the change.
7. Log in to Web GUI. Go to NTP > Sysinfo page. Click
the RESTART button below.
8. Log in to CLI. Type “ntp_query” and press Enter. This
should show now “Queries are restricted and will not be responded to”