diff --git a/nodes/ceph.py b/nodes/ceph.py
index 871b834..c5a9288 100644
--- a/nodes/ceph.py
+++ b/nodes/ceph.py
@@ -16,21 +16,21 @@
     for ip in osd_ips:
         url = "ssh://%s" % ip
         if url in ips:
-            ips[url].add("ceph-osd")
+            ips[url].append("ceph-osd")
         else:
-            ips[url] = ("ceph-osd")
+            ips[url] = ["ceph-osd"]
     for ip in mon_ips:
         url = "ssh://%s" % ip
         if url in ips:
-            ips[url].add("ceph-mon")
+            ips[url].append("ceph-mon")
         else:
-            ips[url] = ("ceph-mon")
+            ips[url] = ["ceph-mon"]
     for ip in mds_ips:
         url = "ssh://%s" % ip
         if url in ips:
-            ips[url].add("ceph-mds")
+            ips[url].append("ceph-mds")
         else:
-            ips[url] = ("ceph-mds")
+            ips[url] = ["ceph-mds"]
 
     res = []
     for url, roles in ips: