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Author: gengliangwang

core/src/main/scala/org/apache/spark/deploy/worker/Worker.scala

@@ -278,10 +278,12 @@ private[deploy] class Worker(
     if (reverseProxy) {
       logInfo("WorkerWebUI is available at %s/proxy/%s".format(
         activeMasterWebUiUrl.stripSuffix("/"), workerId))
-       // if reverseProxyUrl is not set, then we continue to generate relative URLs
-       // starting with "/" throughout the UI and do not use activeMasterWebUiUrl
-       val proxyUrl = conf.get(UI_REVERSE_PROXY_URL.key, "").stripSuffix("/")
-       System.setProperty("spark.ui.proxyBase", proxyUrl)
+      // if reverseProxyUrl is not set, then we continue to generate relative URLs
+      // starting with "/" throughout the UI and do not use activeMasterWebUiUrl
+      val proxyUrl = conf.get(UI_REVERSE_PROXY_URL.key, "").stripSuffix("/")
+      // In the method `UIUtils.makeHref`, the URL segment "/proxy/$worker_id" will be appended
+      // after `proxyUrl`, so no need to set the worker ID in the `spark.ui.proxyBase` here.
+      System.setProperty("spark.ui.proxyBase", proxyUrl)
     }
     // Cancel any outstanding re-registration attempts because we found a new master
     cancelLastRegistrationRetry()