From: Ondřej Surý <ondrej@isc.org>
Date: Wed, 23 Jun 2021 18:54:20 +0000 (+0200)
Subject: Change the safe edns-udp-size from 1400 to 1432
X-Git-Tag: v9.17.16~14^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=4266f6dd2b866a7e8fb23ccaf0d3ad530838feec;p=thirdparty%2Fbind9.git

Change the safe edns-udp-size from 1400 to 1432

When backporting the Don't Fragment UDP socket option, it was noticed
that the edns-udp-size probing uses 1432 as one of the values to be
probed and the documentation would be recommending 1400 as the safe
value.  As the safe value can be from the 1400-1500 interval, the
documentation has been changed to match the probed value, so we do not
skip it.
---

diff --git a/CHANGES b/CHANGES
index 4d16258d695..ce23ac0fb11 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,7 @@
+5666.	[func]		Tweak the safe "edns-udp-size" to match the probing
+			value from BIND 9.16 for better compatibility.
+			[GL #2183]
+
 5665.	[bug]		'nsupdate' did not retry with another server if
 			it received a REFUSED response. [GL #2758]
 
diff --git a/doc/arm/reference.rst b/doc/arm/reference.rst
index a39f4c1d817..f8eb970f10e 100644
--- a/doc/arm/reference.rst
+++ b/doc/arm/reference.rst
@@ -3503,7 +3503,7 @@ Tuning
    a estimated path MTU minus the estimated header space. In practice, the
    smallest MTU witnessed in the operational DNS community is 1500 octets, the
    Ethernet maximum payload size, so a a useful default for maximum DNS/UDP
-   payload size on **reliable** networks would be 1400.
+   payload size on **reliable** networks would be 1432.
 
    Any server-specific ``edns-udp-size`` setting has precedence over all
    the above rules.
diff --git a/doc/notes/notes-9.17.6.rst b/doc/notes/notes-9.17.6.rst
index 974fb83c01b..63bd69da96f 100644
--- a/doc/notes/notes-9.17.6.rst
+++ b/doc/notes/notes-9.17.6.rst
@@ -42,7 +42,7 @@ Feature Changes
   estimated header space. In practice, the smallest MTU witnessed in the
   operational DNS community is 1500 octets, the maximum Ethernet payload
   size, so a useful default for maximum DNS/UDP payload size on reliable
-  networks would be 1400 bytes. :gl:`#2183`
+  networks would be 1432 bytes. :gl:`#2183`
 
 Bug Fixes
 ~~~~~~~~~