Exim crashed for a huge SMTP error response; increasing big_buffer_size

[users/heiko/exim.git] / doc / doc-txt / NewStuff

diff --git a/doc/doc-txt/NewStuff b/doc/doc-txt/NewStuff
index f8e31469df8de8db129be37b9f5d0dccb77fc284..3109ea96faab3cc02de663b835ce48d16058727a 100644 (file)
--- a/doc/doc-txt/NewStuff
+++ b/doc/doc-txt/NewStuff
@@ -1,4 +1,4 @@
-$Cambridge: exim/doc/doc-txt/NewStuff,v 1.18 2004/11/25 13:54:31 ph10 Exp $
+$Cambridge: exim/doc/doc-txt/NewStuff,v 1.21 2004/12/20 15:24:27 ph10 Exp $
 
 New Features in Exim
 --------------------
@@ -9,7 +9,7 @@ updated when there is a relatively large batch of changes). The doc/ChangeLog
 file contains a listing of all changes, including bug fixes.
 
 
-Version 4.44
+Version 4.50
 ------------
 
  1. There is a new build-time option called CONFIGURE_GROUP which works like
@@ -151,9 +151,22 @@ Version 4.44
     default - see 14 below), in the same way that multiple DNS records for a
     single item are handled.
 
-    The lookup fails only if all the DNS lookups fail. As long as at least one
-    of them yields some data, the lookup succeeds. However, if there is a
-    temporary DNS error for any of them, the lookup defers.
+    The dnsdb lookup fails only if all the DNS lookups fail. If there is a
+    temporary DNS error for any of them, the behaviour is controlled by
+    an optional keyword followed by a comma that may appear before the record
+    type. The possible keywords are "defer_strict", "defer_never", and
+    "defer_lax". With "strict" behaviour, any temporary DNS error causes the
+    whole lookup to defer. With "never" behaviour, a temporary DNS error is
+    ignored, and the behaviour is as if the DNS lookup failed to find anything.
+    With "lax" behaviour, all the queries are attempted, but a temporary DNS
+    error causes the whole lookup to defer only if none of the other lookups
+    succeed. The default is "lax", so the following lookups are equivalent:
+
+      ${lookup dnsdb{defer_lax,a=one.host.com:two.host.com}}
+      ${lookup dnsdb{a=one.host.com:two.host.com}}
+
+    Thus, in the default case, as long as at least one of the DNS lookups
+    yields some data, the dnsdb lookup succeeds.
 
 15. It is now possible to specify the character to be used as a separator when
     a dnsdb lookup returns data from more than one DNS record. The default is a
@@ -198,7 +211,11 @@ Version 4.44
        2.1.168.192.black.list.tld  and  a.domain.black.list.tld
 
     Once a DNS record has been found (that matches a specific IP return
-    address, if specified), no further lookups are done.
+    address, if specified), no further lookups are done. If there is a
+    temporary DNS error, the rest of the sublist of domains or IP addresses is
+    tried. The dnslists item itself defers only if none of the other DNS
+    lookups in this sublist succeeds. In other words, a successful lookup for
+    any of the items in the sublist overrides a defer for a previous item.
 
 17. The log selector queue_time_overall causes Exim to output the time spent on
     the queue as an addition to the "Completed" message. Like queue_time (which
@@ -214,6 +231,9 @@ Version 4.44
     This is helpful when the system filter adds header lines or sets filter
     variables that are used by the user filter.
 
+19. The Exiscan patch is now merged into the main source. See src/EDITME for
+    parameters for the build.
+
 
 Version 4.43
 ------------