This problem occurs when you use update manager to
install an update that requires a system reboot on a managed system
that forbids all ICMP packages.
Problem
When
you apply an update package that requires a system reboot during the
update task to a managed system that forbids ICMP packages, the task
reports "A failure occurred when trying to restart system". The
task then completes with errors when the timeout threshold is reached.
Explanation
Some systems in your environment are potentially
configured to forbid all ICMP packages. For example, you cannot reach
such systems with the ping command. During update
tasks that initiate a managed system reboot, update manager checks
for a successful restart by sending ICMP packages to the system. If
ICMP packages are banned, the check is unsuccessful, and update manager cannot
verify that the system restarted.
Resolution
To
resolve this issue, configure the managed system to allow ICMP traffic.
Alternatively, you can ignore the error message and just check the
system restart status manually.