Fault Symptom
The
destination IP specified in an NQA test instance becomes unreachable, but the
static route associated with NQA still exists in the AR's routing table without
being withdrawn.
[AR1]display nqa history
NQA entry(test, test) history:
Index T/H/P Response
Status
Address
Time
1 325/1/1 3000ms
timeout 13.13.13.2
2014-02-28 04:13.367
2 326/1/1 3000ms timeout
13.13.13.2 2014-02-28 04:13.287
3 327/1/1 3000ms
timeout 13.13.13.2
2014-02-28 04:13.367
The static route still exists without being withdrawn.
[AR1]display ip routing-table
Route Flags:
R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Tables: Public
Destinations :
12 Routes :
12
Destination/Mask Proto Pre
Cost Flags
NextHop Interface
1.1.1.1/32 Direct
0
0 D
127.0.0.1 LoopBack0
3.3.3.3/32 Static
60 0
RD 13.13.13.2 GigabitEthernet0/0/1
Alarm Information
None
Troubleshooting Procedure
Check that
the NQA test result displays no result.
<AR1>display nqa result
NQA entry(test, test) :testflag is active ,testtype is icmp
1 . Test 461 result The test is finished
Send operation times:
2
Receive response times: 0
Completion:no
result
RTD OverThresholds number: 0
Attempts
number:1
Drop operation
number:0
Disconnect operation
number:0 Operation timeout
number:1
System busy operation number:0
Connection fail
number:0
Operation sequence errors number:0 RTT Status errors
number:0
Destination ip
address:13.13.13.2
Min/Max/Average Completion Time:
0/0/0
Sum/Square-Sum Completion Time:
0/0
Last Good Probe Time: 2014-02-28 04:13.0
2. Why the destination IP address in the NQA test instance times out but the
NQA test result is still no result? Check the NQA configuration:
[AR1] display current-configuration configuration
nqa
[V200R003C00]
#
nqa test-instance test test
test-type icmp
destination-address ipv4 13.13.13.2
frequency 5
start now
3. Find that frequency 5 is
configured in NQA, indicating that the test frequency is 5s. However, the
default probe-count is 3, indicating that each test requires three packets to
be sent and the result to be returned.
Therefore, when the destination IP address has been interrupted. Three ping
packet detections cannot be completed with the period of 5s. As a result, the
NQA test result is no result. The associated route cannot be withdrawn.
4. Change the frequency to 20s or change the probe-count to 1. The NQA test
result displays failed, and the
associated static route is withdrawn.
Root Cause
A static route associated with NQA is withdrawn only when the NQA test result displays failed. If the display nqa history command output displays timeout, it does not indicate that the NQA test result is failed.
Summary and Suggestions
A static route associated with NQA is withdrawn only when the NQA test result displays failed.