Replication #NA2: Discrepancy between master_repl_offset and “REPLCONF ACK”

Challenges
1

Hi, I need help understanding why there is a discrepancy between my master_repl_offset (68) and the value from REPLCONF ACK (197).

In this case, my master only sent a SET (31) and a GETACK (37) to replicas, making my master_repl_offset 68 = 31 + 37.

But why would a replica send REPLCONF ACK 197 back to my master? How could it be bigger than 68?

Thanks!

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3

Hey @andy1li!

Thanks for reporting this, can confirm that this is a bug on our end. We were incorrectly including the handshake bytes in the count.

We have a fix for this here that should be deployed shortly:

I’ll update this thread once the fix is out.

Once the fix is out, in the example you shared, for the first GETACK the expected response will be 31 (an ACK only includes bytes processed before the current GETACK).

1 Like
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The fix should be deployed now!

1 Like
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Note: I’ve updated the title of this post to include the stage ID (#NA2). You can learn about the stages rename here: Upcoming change: Stages overhaul