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+# ONLINE Command
+
+Displays all volumes online.
+
+    ]ONLINE
+    
+    S3,D2 /RAM
+    S6,D1 ERR=$27
+    S6,D2 ERR=$27
+    
+
+Accepts slot/drive parameters.
+
+    ]ONLINE,S3,D2
+    
+    S3,D2 /RAM
+    
+
+Error code of $57 indicates duplicate volumes are online, and ONLINE reports which disk is a duplicate.
+
+    ]ONLINE
+    
+    S6,D1 /MY.DISK
+    S6,D2 ERR=$57 (S6,D1)
+    
+