[FIXED JENKINS-2548] Slaves taken offline for low disk space will now

come back online when disk space becomes available.

changelog.html

@@ -85,6 +85,9 @@ Upcoming changes</a>
   <li class=bug>
     Use $JENKINS_USER in Debian postinst script.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-5771">issue 5771</a>)
+  <li class=bug>
+    Slaves taken offline due to insufficient disk space should automatically come back online when disk space is cleared.
+    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-2548">issue 2548</a>)
 </ul>
 </div><!--=TRUNK-END=-->
 

core/src/main/java/hudson/node_monitors/AbstractDiskSpaceMonitor.java

@@ -45,6 +45,10 @@ public abstract class AbstractDiskSpaceMonitor extends NodeMonitor {
         	if(getDescriptor().markOffline(c,size)) {
         		LOGGER.warning(Messages.DiskSpaceMonitor_MarkedOffline(c.getName()));
         	}
+        } else if (c.isTemporarilyOffline()) {
+            if (getDescriptor().markOnline(c)) {
+                LOGGER.warning(Messages.DiskSpaceMonitor_MarkedOnline(c.getName()));
+            }
         }
         return size;
     }

core/src/main/java/hudson/node_monitors/AbstractNodeMonitorDescriptor.java

@@ -148,6 +148,21 @@ public abstract class   AbstractNodeMonitorDescriptor<T> extends Descriptor<Node
         return true;
     }
 
+
+    /**
+     * Utility method to mark the computer online for derived classes.
+     *
+     * @return true
+     *      if the node was actually brought back online - false if the node was already online.
+     */
+    protected boolean markOnline(Computer c) {
+        if (!c.isTemporarilyOffline()) return false; // noop
+
+        c.setTemporarilyOffline(false);
+
+        return true;
+    }
+
     /**
      * @deprecated as of 1.320
      *      Use {@link #markOffline(Computer, OfflineCause)} to specify the cause.

core/src/main/resources/hudson/node_monitors/Messages.properties

@@ -23,6 +23,7 @@
 ArchitectureMonitor.DisplayName=Architecture
 ClockMonitor.DisplayName=Clock Difference
 DiskSpaceMonitor.MarkedOffline=Making {0} offline temporarily due to the lack of disk space
+DiskSpaceMonitor.MarkedOnline=Bringing {0} online due to disk space recovery
 DiskSpaceMonitor.DisplayName=Free Disk Space
 ResponseTimeMonitor.DisplayName=Response Time
 ResponseTimeMonitor.MarkedOffline=Making {0} offline because it''s not responding