at first need to check the Relevant Alarm (No response from radius accounting server)
Service impacted alarm
How to check
System-view
Access-view
test aaaip10.163.145.242account vpn-instance gpinternet
[SVGGSN01-access]test aaaip10.163.145.242 account vpn-instance gpinternet
Test radius server on SPU board 8 CPU 0 success!
Test radius server on SPU board 8 CPU 1 success!

success means response received.