diff --git a/PendingReleaseNotes b/PendingReleaseNotes
index 4bd1329589e64..8959684cd9961 100644
--- a/PendingReleaseNotes
+++ b/PendingReleaseNotes
@@ -10,3 +10,14 @@
   New monitors will now use rocksdb by default, but if that file is
   not present, existing monitors will use leveldb.  The ``mon keyvaluedb`` option
   now only affects the backend chosen when a monitor is created.
+
+* The 'osd crush initial weight' option allows you to specify a CRUSH
+  weight for a newly added OSD.  Previously a value of 0 (the default)
+  meant that we should use the size of the OSD's store to weight the
+  new OSD.  Now, a value of 0 means it should have a weight of 0, and
+  a negative value (the new default) means we should automatically
+  weight the OSD based on its size.  If your configuration file
+  explicitly specifies a value of 0 for this option you will need to
+  change it to a negative value (e.g., -1) to preserve the current
+  behavior.
+
diff --git a/src/common/config_opts.h b/src/common/config_opts.h
index a6227e9a56a0e..516142b224bd7 100644
--- a/src/common/config_opts.h
+++ b/src/common/config_opts.h
@@ -614,7 +614,7 @@ OPTION(osd_pgp_bits, OPT_INT, 6)  // bits per osd
 OPTION(osd_crush_chooseleaf_type, OPT_INT, 1) // 1 = host
 OPTION(osd_pool_use_gmt_hitset, OPT_BOOL, true) // try to use gmt for hitset archive names if all osds in cluster support it.
 OPTION(osd_crush_update_on_start, OPT_BOOL, true)
-OPTION(osd_crush_initial_weight, OPT_DOUBLE, 0) // the initial weight is for newly added osds.
+OPTION(osd_crush_initial_weight, OPT_DOUBLE, -1) // if >=0, the initial weight is for newly added osds.
 OPTION(osd_pool_default_crush_rule, OPT_INT, -1) // deprecated for osd_pool_default_crush_replicated_ruleset
 OPTION(osd_pool_default_crush_replicated_ruleset, OPT_INT, CEPH_DEFAULT_CRUSH_REPLICATED_RULESET)
 OPTION(osd_pool_erasure_code_stripe_width, OPT_U32, OSD_POOL_ERASURE_CODE_STRIPE_WIDTH) // in bytes
diff --git a/src/osd/OSD.cc b/src/osd/OSD.cc
index bc12f78356948..0dde567091eca 100644
--- a/src/osd/OSD.cc
+++ b/src/osd/OSD.cc
@@ -2766,7 +2766,7 @@ int OSD::update_crush_location()
   }
 
   char weight[32];
-  if (g_conf->osd_crush_initial_weight) {
+  if (g_conf->osd_crush_initial_weight >= 0) {
     snprintf(weight, sizeof(weight), "%.4lf", g_conf->osd_crush_initial_weight);
   } else {
     struct statfs st;