diff --git a/installers/charm/mon/config.yaml b/installers/charm/mon/config.yaml
index 5391497..f6d1ae1 100644
--- a/installers/charm/mon/config.yaml
+++ b/installers/charm/mon/config.yaml
@@ -76,3 +76,11 @@
     description: MON will use Keystone backend
     type: boolean
     default: false
+  certificates:
+    type: string
+    description: |
+      comma-separated list of <name>:<content> certificates.
+      Where:
+        name: name of the file for the certificate
+        content: base64 content of the certificate
+      The path for the files is /certs.