perfSONAR User Q&A and Other Discussion

[Eli Dart <>]

Hi Brian,

Just out of curiosity, why would you trust ping to measure latency if you're not satisfied with OWAMP?

If NTP clock skew is causing you problems, I'm guessing you're measuring latency over very short distances, but I'd like to ask before I assume.  What sort of network are you trying to measure?  I apologize if I've missed it in earlier threads.

Eli

On Fri, Dec 5, 2014 at 10:18 AM, Brian Candler <> wrote:

I'm finding that the latencies I'm trying to measure are less than the differences in NTP-synced time, and this leads to very misleading graphs.

1. Does anyone have any suggestions for a good, but not-too-expensive, GPS time source to use with perfsonar/CentOS?

2. Is it possible to configure perfsonar to graph the sensitive packet loss from owamp, but hide the latency? (I can always use ping for round-trip latency)

Thanks,

Brian.

--

Eli Dart, Network Engineer                          NOC: (510) 486-7600

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