In pg_upgrade, document that link mode has to have data directories on

the same file system, and that authentication should lock out normal
users.

Per suggestsion from #postgresql irc channel.

Backpatch to 9.1.

diff --git a/doc/src/sgml/pgupgrade.sgml b/doc/src/sgml/pgupgrade.sgml
index 8bd5f74178e8d70e3b60093900c1223796b92257..a505707cc0112edc47181ad532e8064fa61ac24f 100644 (file)
--- a/doc/src/sgml/pgupgrade.sgml
+++ b/doc/src/sgml/pgupgrade.sgml
@@ -256,7 +256,8 @@ gmake prefix=/usr/local/pgsql.new install
      so you might want to set authentication to trust in
      pg_hba.conf, or if using md5 authentication,
      use a ~/.pgpass file (see )
-     to avoid being prompted repeatedly for a password.
+     to avoid being prompted repeatedly for a password.  Also make sure
+     pg_upgrade is the only program that can connect to the clusters.
     
    
 
@@ -295,9 +296,11 @@ NET STOP pgsql-8.3  (PostgreSQL 8.3 and older used a different s
      data and executable (bin) directories. You can also specify separate
      user and port values, and whether you want the data linked instead of
      copied (the default). If you use linking, the upgrade will be much
-     faster (no data copying), but you will no longer be able to access your
-     old cluster once you start the new cluster after the upgrade. See
-     pg_upgrade --help for a full list of options.
+     faster (hard link data files rather than copying them), but you
+     will no longer be able to access your old cluster once you start
+     the new cluster after the upgrade.  Link mode also requires that the
+     old and new cluster data directories be in the same file system.
+     See pg_upgrade --help for a full list of options.