--- /dev/null
+ $ ceph-authtool kring --create-keyring
+ creating kring
+
+ $ ceph-authtool kring --add-key 'AQAK7yxNeF+nHBAA0SgSdbs8IkJrxroDeJ6SwQ== 18446744073709551615'
+ added entity client.admin auth auth(auid = 18446744073709551615 key=AQAK7yxNeF+nHBAA0SgSdbs8IkJrxroDeJ6SwQ== with 0 caps)
+
+# cram makes matching escape-containing lines with regexps a bit ugly
+ $ ceph-authtool kring --list
+ [client.admin]
+ \tkey = AQAK7yxNeF+nHBAA0SgSdbs8IkJrxroDeJ6SwQ== (esc)
+
+ $ cat kring
+ [client.admin]
+ \tkey = AQAK7yxNeF+nHBAA0SgSdbs8IkJrxroDeJ6SwQ== (esc)
+
+Test --add-key with empty argument
+
+ $ ceph-authtool kring -C --name=mon.* --add-key= --cap mon 'allow *'
+ Option --add-key requires an argument
+ [1]