website: quickstart for generic

website/source/docs/secrets/generic/index.html.md

@@ -17,4 +17,31 @@ via the `secret/` prefix that Vault mounts by default.
 
 ## Quick Start
 
-TODO
+The generic backend allows for writing keys with arbitrary values. The
+only value that special is the `lease` key, which can be provided with
+any key to restrict the lease time of the secret. This is useful to ensure
+clients periodically renew so that key rolling can be time bounded.
+
+As an example, we can write a new key "foo" to the generic backend
+mounted at "secret/" by default:
+
+```
+$ vault write secret/foo zip=zap lease=1h
+Success! Data written to: secret/foo
+```
+
+This writes the key with the "zip" field set to "zap" and a one hour lease. We can test
+this by doing a read:
+
+```
+$ vault read secret/foo
+Key           	Value
+lease_id      	secret/foo/e4514713-d5d9-fb14-4177-97a7f7f64518
+lease_duration	3600
+lease         	1h
+zip           	zap
+```
+
+As expected, we get the value previously set back as well as our custom lease.
+The lease_duration has been set to 3600 seconds, or one hour as specified.
+