You can update Sensor software either via a Manager or a TFTP server. It's important to know the differences between the two and the issues that can arise by a TFTP update, especially when you perform a major version upgrade. For example, a major upgrade would be upgrading from version 9.1 to 10.1
When you update a Sensor via the Manager, both the Sensor software and the sigset are bundled together and sent to the Sensor. The Sensor updates its software, reboots, and then applies the sigset that has been stored on the Sensor.
When updating a Sensor via TFTP, only the Sensor software is transferred across. After updating its software, the Sensor reboots. When the Sensor reboots, it deletes the sigset that's currently loaded, and then contacts the Manager for the most current sigset. So, the delay to bring up the Sensor to working order is much longer with a TFTP update.
IMPORTANT: We recommend that you always update the Sensor software via the Manager for any major upgrade.
