17590: Add upgrade note about changed config keys.

Arvados-DCO-1.1-Signed-off-by: Tom Clegg <tom@curii.com>

diff --git a/doc/admin/upgrading.html.textile.liquid b/doc/admin/upgrading.html.textile.liquid
index 52b71287b2c27af49537c9461255a1c6d6bac52f..6d1736fb56eb28ca33d03c8b9e45b24b3cac5ca1 100644 (file)
--- a/doc/admin/upgrading.html.textile.liquid
+++ b/doc/admin/upgrading.html.textile.liquid
@@ -39,6 +39,10 @@ h2(#main). development main (as of 2020-12-10)
 
 "Upgrading from 2.1.0":#v2_1_0
 
+h3. New spelling of S3 credential configs
+
+If you use the S3 driver for Keep volumes and specify credentials in your configuration file (as opposed to using an IAM role), you should change the spelling of the @AccessKey@ and @SecretKey@ config keys to @AccessKeyID@ and @SecretAccessKey@. If you don't update them, the previous spellings will still be accepted, but warnings will be logged at server startup.
+
 h3. New proxy parameters for arvados-controller
 
 In your Nginx configuration file (@/etc/nginx/conf.d/arvados-api-and-controller.conf@), add the following lines to the @location /@ block with @http://controller@ (see "Update nginx configuration":{{site.baseurl}}/install/install-api-server.html#update-nginx for an example) and reload/restart Nginx (@sudo nginx -s reload@).