diff --git a/utils/misc/src/main/java/org/onlab/util/Tools.java b/utils/misc/src/main/java/org/onlab/util/Tools.java
index 4b2cac9..69baf47 100644
--- a/utils/misc/src/main/java/org/onlab/util/Tools.java
+++ b/utils/misc/src/main/java/org/onlab/util/Tools.java
@@ -388,6 +388,7 @@
         try {
             Thread.sleep(ms);
         } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
             throw new IllegalStateException("Interrupted", e);
         }
     }
@@ -460,6 +461,7 @@
         try {
             Thread.sleep(random.nextInt(ms));
         } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
             throw new IllegalStateException("Interrupted", e);
         }
     }
@@ -474,6 +476,7 @@
         try {
             Thread.sleep(ms, nanos);
         } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
             throw new IllegalStateException("Interrupted", e);
         }
     }