From ce79ea342cf6e7e150af628e8b4723863e4dce35 Mon Sep 17 00:00:00 2001 From: Matthijs Mekking Date: Thu, 21 Jan 2021 15:18:09 +0000 Subject: [PATCH] Update Serving stale data --- Serving-stale-data.md | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/Serving-stale-data.md b/Serving-stale-data.md index 80e9ea1..895f2d0 100644 --- a/Serving-stale-data.md +++ b/Serving-stale-data.md @@ -57,6 +57,33 @@ All improvements made in 9.16.9 and later will be backported to 9.11-S1. ## A client walks into a bar, and asks the bartender do you have stale data? +| stale-cache-enable | stale-answer-enable | stale-refresh-time | stale-answer-client-timeout | +| ------------------ | ------------------- | ------------------ | --------------------------- | +| no | no | 0 (disabled) | off (disabled) | +| no | no | 0 (disabled) | 0 | +| no | no | 0 (disabled) | value | +| no | no | value | off (disabled) | +| no | no | value | 0 | +| no | no | value | value | +| no | yes | 0 (disabled) | off (disabled) | +| no | yes | 0 (disabled) | 0 | +| no | yes | 0 (disabled) | value | +| no | yes | value | off (disabled) | +| no | yes | value | 0 | +| no | yes | value | value | +| yes | no | 0 (disabled) | off (disabled) | +| yes | no | 0 (disabled) | 0 | +| yes | no | 0 (disabled) | value | +| yes | no | value | off (disabled) | +| yes | no | value | 0 | +| yes | no | value | value | +| yes | yes | 0 (disabled) | off (disabled) | +| yes | yes | 0 (disabled) | 0 | +| yes | yes | 0 (disabled) | value | +| yes | yes | value | off (disabled) | +| yes | yes | value | 0 | +| yes | yes | value | value | + With all these options, we now allow operators to be RFC 8767 compliant. But it is also less predictable when stale data is returned and when an attempt to resolve the query is made. If `stale-cache-enable` is set to `no`, stale data is not kept in cache and it will not be used in DNS responses. It does not matter what the other options are set to, they are ignored in this case.