Are there any recommendations, or things to look for, to correct udp jitter probes returning zero one way latency values? What are the determining factors for NTP to be out of spec for instance? Documentation on Cisco's site is very vague, curious to see how many others have encountered/fixed this type of issue. Here is what my probes typically show -
rtr-01#sh ip sla stat 2
IPSLAs Latest Operation Statistics
IPSLA operation id: 2
Type of operation: udp-jitter
Latest RTT: 1 milliseconds
Latest operation start time: 16:33:06 UTC Thu Mar 20 2014
Latest operation return code: OK
RTT Values:
Number Of RTT: 50 RTT Min/Avg/Max: 1/1/1 milliseconds
Latency one-way time:
Number of Latency one-way Samples: 0
Source to Destination Latency one way Min/Avg/Max: 0/0/0 milliseconds
Destination to Source Latency one way Min/Avg/Max: 0/0/0 milliseconds
Jitter Time:
Number of SD Jitter Samples: 49
Number of DS Jitter Samples: 49
Source to Destination Jitter Min/Avg/Max: 0/1/1 milliseconds
Destination to Source Jitter Min/Avg/Max: 0/286/1000 milliseconds
Over Threshold:
Number Of RTT Over Threshold: 0 (0%)
Packet Loss Values:
Loss Source to Destination: 0
Source to Destination Loss Periods Number: 0
Source to Destination Loss Period Length Min/Max: 0/0
Source to Destination Inter Loss Period Length Min/Max: 0/0
Loss Destination to Source: 0
Destination to Source Loss Periods Number: 0
Destination to Source Loss Period Length Min/Max: 0/0
Destination to Source Inter Loss Period Length Min/Max: 0/0
Out Of Sequence: 0 Tail Drop: 0
Packet Late Arrival: 0 Packet Skipped: 0
Voice Score Values:
Calculated Planning Impairment Factor (ICPIF): 1
MOS score: 4.34
Number of successes: 349
Number of failures: 0
Operation time to live: Forever
rtr-01#
rtr-01#sh ntp status
Clock is synchronized, stratum 3, reference is 127.127.1.1
nominal freq is 250.0000 Hz, actual freq is 249.9830 Hz, precision is 2**10
ntp uptime is 266584600 (1/100 of seconds), resolution is 4016
reference time is D6D59727.824DD458 (16:34:47.509 UTC Thu Mar 20 2014)
clock offset is 0.0000 msec, root delay is 0.00 msec
root dispersion is 2.25 msec, peer dispersion is 1.20 msec
loopfilter state is 'CTRL' (Normal Controlled Loop), drift is 0.000067971 s/s
system poll interval is 16, last update was 5 sec ago.
rtr-01#
