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+# Volume operations
+
+### Changing replica count of the volumes
+
+The default replica count can be changed in the setting.
+
+Also, when a volume is attached, the user can change the replica count for the volume in the UI.
+
+Longhorn will always try to maintain at least given number of healthy replicas for each volume. If the current healthy 
+replica count is less than specified replica count, Longhorn will start rebuilding new replicas. If the current healthy 
+replica count is more than specified replica count, Longhorn will do nothing. In the later situation, if user delete one 
+or more healthy replicas, or there are healthy replicas failed, as long as the total healthy replica count doesn't dip 
+below the specified replica count, Longhorn won't start rebuilding new replicas.