diff --git a/DEPLOYMENT-NOTES.rst b/DEPLOYMENT-NOTES.rst
index 5de83386dbb939cc3cfe2a8b68c198f218934933..0a7ea52e0bfb20e77f86797ead1778d614a2a720 100644
--- a/DEPLOYMENT-NOTES.rst
+++ b/DEPLOYMENT-NOTES.rst
@@ -1,6 +1,8 @@
 Deployment notes
 ================
 
+- 2021-09-30 `Enable alerting <https://whetstone.privatestorage.io/privatestorage/PrivateStorageio/-/merge_requests/185>`_ needs a secret in ``private-keys/grafana-slack-url`` looking like the template in ``morph/grid/local/private-keys/grafana-slack-url`` and pointing to the secret API endpoint URL saved in `this 1Password entry <https://privatestorage.1password.com/vaults/7flqasy5hhhmlbtp5qozd3j4ga/allitems/cgznskz2oix2tyx5xyntwaos5i>`_ (or create a new secret URL at https://www.slack.com/apps/A0F7XDUAZ).
+
 - 2021-09-07 `Manage access to payment metrics <https://whetstone.privatestorage.io/privatestorage/PrivateStorageio/-/merge_requests/146>`_ requires moving and chown'ing the PaymentServer database on the ``payments`` host::
 
    mkdir /var/lib/zkapissuer