[master] clarify edns-udp-size doc

diff --git a/doc/arm/Bv9ARM-book.xml b/doc/arm/Bv9ARM-book.xml
index 32c240e4caf3804bf35200b5163758df7d68cd46..48171cc19bb8c1bfed11ba8f7d92ead27dcb9c5e 100644 (file)
--- a/doc/arm/Bv9ARM-book.xml
+++ b/doc/arm/Bv9ARM-book.xml
@@ -8980,7 +8980,7 @@ avoid-v6-udp-ports { 40000; range 50000 60000; };
              <term><command>edns-udp-size</command></term>
              <listitem>
                <para>
-                 Sets the initial advertised EDNS UDP buffer size in
+                 Sets the maximum advertised EDNS UDP buffer size in
                  bytes, to control the size of packets received from
                  authoritative servers in response to recursive queries.
                  Valid values are 512 to 4096 (values outside this range
@@ -10639,7 +10639,15 @@ example.com                 CNAME   rpz-tcp-only.
            is useful when you wish to advertise a different value
            to this server than the value you advertise globally,
            for example, when there is a firewall at the remote
-           site that is blocking large replies.
+           site that is blocking large replies. (Note: Currently,
+           this sets a single UDP size for all packets sent to the
+           server; <command>named</command> will not deviate from
+           this value.  This differs from the behavior of
+           <command>edns-udp-size</command> in <command>options</command>
+           or <command>view</command> statements, where it specifies
+           a maximum value. The <command>server</command> statement
+           behavior may be brought into conformance with the
+           <command>options/view</command> behavior in future releases.)
          </para>
 
          <para>