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The above shows that the clock on flux agrees to within a maximum 52 microseconds with each DSM, as indicated by the "Last sample" value in brackets, which is the estimated last calculated offset of the DSM time from the system time on flux.
The second character should be '*' (chrony on flux is sync'd to this server) or '+' (good server). You may also see '-' (recently on 100m for some reason) indicating chrony does not have a high opinion of its time information, relative to the others.
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