98 CHAPTER 11: S OFTWARE UPGRADE AND INSTALLATIONThe configuration of the Webcache is preserved after a software upgradehas been performed; you do not have to re-configure the settings.3Com recommends that you configure the Webcache to automaticallydetect new software versions.Software UpgradeSNMP TrapsAn SNMP Trap is sent to your network management station when any ofthe following events occur: When the software upgrade server is not available and automaticsoftware upgrade detection is enabled. A new software upgrade is detected. A software upgrade is successful.If the software upgrade is completed successfully, the trap indicatesthat the upgrade has been successful and tells you what softwareversion the Webcache is now running. A software upgrade fails.If the software upgrade is completed unsuccessfully, the trap indicatesthat the upgrade has been unsuccessful and tells you why it failed.For more information about SNMP Traps, see “SNMP Traps” on page 85.UnsuccessfulSoftware UpgradesThe Webcache software upgrade process is robust and guards against anupgrade failure. Should a software upgrade fail, the Webcache willautomatically revert to using the software version that was installedbefore the upgrade was started. The upgrade process is resilient to powerfailure, network failure or system failure. Prior to offering an automaticsoftware upgrade, the Webcache will download the new softwareversion onto temporary storage on the Webcache, ensuring that thecomplete software image file is available before commencing theupgrade.Detecting SoftwareUpgradesTo configure the detection of software upgrades using the Web interface:1 Click Device View on the Toolbar.2 Select System > Control > Upgrade Settings in the Navigation Tree.
