[ https://issues.apache.org/jira/browse/HDFS-17166?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17760256#comment-17760256 ]
ASF GitHub Bot commented on HDFS-17166: --------------------------------------- hadoop-yetus commented on PR #5990: URL: https://github.com/apache/hadoop/pull/5990#issuecomment-1698613947 :broken_heart: **-1 overall** | Vote | Subsystem | Runtime | Logfile | Comment | |:----:|----------:|--------:|:--------:|:-------:| | +0 :ok: | reexec | 0m 28s | | Docker mode activated. | |||| _ Prechecks _ | | +1 :green_heart: | dupname | 0m 1s | | No case conflicting files found. | | +0 :ok: | codespell | 0m 0s | | codespell was not available. | | +0 :ok: | detsecrets | 0m 0s | | detect-secrets was not available. | | +1 :green_heart: | @author | 0m 0s | | The patch does not contain any @author tags. | | +1 :green_heart: | test4tests | 0m 0s | | The patch appears to include 3 new or modified test files. | |||| _ trunk Compile Tests _ | | +1 :green_heart: | mvninstall | 31m 26s | | trunk passed | | +1 :green_heart: | compile | 0m 32s | | trunk passed with JDK Ubuntu-11.0.20+8-post-Ubuntu-1ubuntu120.04 | | +1 :green_heart: | compile | 0m 30s | | trunk passed with JDK Private Build-1.8.0_382-8u382-ga-1~20.04.1-b05 | | +1 :green_heart: | checkstyle | 0m 25s | | trunk passed | | +1 :green_heart: | mvnsite | 0m 33s | | trunk passed | | +1 :green_heart: | javadoc | 0m 35s | | trunk passed with JDK Ubuntu-11.0.20+8-post-Ubuntu-1ubuntu120.04 | | +1 :green_heart: | javadoc | 0m 26s | | trunk passed with JDK Private Build-1.8.0_382-8u382-ga-1~20.04.1-b05 | | +1 :green_heart: | spotbugs | 1m 0s | | trunk passed | | -1 :x: | shadedclient | 22m 58s | | branch has errors when building and testing our client artifacts. | |||| _ Patch Compile Tests _ | | +1 :green_heart: | mvninstall | 0m 24s | | the patch passed | | +1 :green_heart: | compile | 0m 25s | | the patch passed with JDK Ubuntu-11.0.20+8-post-Ubuntu-1ubuntu120.04 | | +1 :green_heart: | javac | 0m 25s | | the patch passed | | +1 :green_heart: | compile | 0m 23s | | the patch passed with JDK Private Build-1.8.0_382-8u382-ga-1~20.04.1-b05 | | +1 :green_heart: | javac | 0m 23s | | the patch passed | | +1 :green_heart: | blanks | 0m 0s | | The patch has no blanks issues. | | +1 :green_heart: | checkstyle | 0m 14s | | the patch passed | | +1 :green_heart: | mvnsite | 0m 24s | | the patch passed | | +1 :green_heart: | javadoc | 0m 22s | | the patch passed with JDK Ubuntu-11.0.20+8-post-Ubuntu-1ubuntu120.04 | | +1 :green_heart: | javadoc | 0m 20s | | the patch passed with JDK Private Build-1.8.0_382-8u382-ga-1~20.04.1-b05 | | +1 :green_heart: | spotbugs | 0m 54s | | the patch passed | | -1 :x: | shadedclient | 23m 21s | | patch has errors when building and testing our client artifacts. | |||| _ Other Tests _ | | +1 :green_heart: | unit | 19m 27s | | hadoop-hdfs-rbf in the patch passed. | | +1 :green_heart: | asflicense | 0m 31s | | The patch does not generate ASF License warnings. | | | | 108m 38s | | | | Subsystem | Report/Notes | |----------:|:-------------| | Docker | ClientAPI=1.43 ServerAPI=1.43 base: https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-5990/6/artifact/out/Dockerfile | | GITHUB PR | https://github.com/apache/hadoop/pull/5990 | | Optional Tests | dupname asflicense compile javac javadoc mvninstall mvnsite unit shadedclient spotbugs checkstyle codespell detsecrets | | uname | Linux c842325ffa1f 4.15.0-213-generic #224-Ubuntu SMP Mon Jun 19 13:30:12 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux | | Build tool | maven | | Personality | dev-support/bin/hadoop.sh | | git revision | trunk / ff812317821414e9758f8d441e21aee826d75207 | | Default Java | Private Build-1.8.0_382-8u382-ga-1~20.04.1-b05 | | Multi-JDK versions | /usr/lib/jvm/java-11-openjdk-amd64:Ubuntu-11.0.20+8-post-Ubuntu-1ubuntu120.04 /usr/lib/jvm/java-8-openjdk-amd64:Private Build-1.8.0_382-8u382-ga-1~20.04.1-b05 | | Test Results | https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-5990/6/testReport/ | | Max. process+thread count | 2567 (vs. ulimit of 5500) | | modules | C: hadoop-hdfs-project/hadoop-hdfs-rbf U: hadoop-hdfs-project/hadoop-hdfs-rbf | | Console output | https://ci-hadoop.apache.org/job/hadoop-multibranch/job/PR-5990/6/console | | versions | git=2.25.1 maven=3.6.3 spotbugs=4.2.2 | | Powered by | Apache Yetus 0.14.0 https://yetus.apache.org | This message was automatically generated. > RBF: Throwing NoNamenodesAvailableException for a long time, when failover > -------------------------------------------------------------------------- > > Key: HDFS-17166 > URL: https://issues.apache.org/jira/browse/HDFS-17166 > Project: Hadoop HDFS > Issue Type: Bug > Reporter: Jian Zhang > Priority: Major > Labels: pull-request-available > Attachments: HDFS-17166.001.patch, HDFS-17166.002.patch, > HDFS-17166.003.patch, HDFS-17166.004.patch, HDFS-17166.005.patch, > image-2023-08-26-11-48-22-131.png, image-2023-08-26-11-56-50-181.png, > image-2023-08-26-11-59-25-153.png, image-2023-08-26-12-01-39-968.png, > image-2023-08-26-12-06-01-275.png, image-2023-08-26-12-07-47-010.png, > image-2023-08-26-22-45-46-814.png, image-2023-08-26-22-47-22-276.png, > image-2023-08-26-22-47-41-988.png, image-2023-08-26-22-48-02-086.png, > image-2023-08-26-22-48-12-352.png > > > When ns failover, the router may record that the ns have no active namenode, > the router cannot find the active nn in the ns for about 1 minute. The client > will report an error after consuming the number of retries, and the router > will be unable to provide services for the ns for a long time. > 11:52:44 Start reporting > !image-2023-08-26-12-06-01-275.png|width=800,height=100! > 11:53:46 end reporting > !image-2023-08-26-12-07-47-010.png|width=800,height=20! > > At this point, the failover has been successfully completed in the ns, and > the client can directly connect to the active namenode to access it > successfully, but the client cannot access the ns through router for up to a > minute > > *There is a bug in this logic:* > * A certain ns starts to fail over, > * There is a state where there is no active nn in ns, Router reports the > status (no active nn) to the state store > * After a period of time, the router pulls the state store data to update > the cache, and the cache records that the ns has no active nn > * Failover successfully completed, at which point the ns actually has an > active nn > * Assuming it's not time for router to update the cache yet > * The client sent a request to the router for the ns, and the router > accessed the first nn of the ns in the router’s cache (no active nn) > * Unfortunately, the nn is really standby, so the request went wrong and > entered the exception handling logic. The router found that there is no > active nn for the ns in the cache and throw NoNamenodesAvailableException > * The NoNamenodesAvailableException exception is wrapped as a > RetrieveException, which causes the client to retry. Since each router > retrieves the true standby nn in the cache (because it is always the first > one in the cache and has a high priority), a NoNamenodesAvailableException is > thrown every time until the router updates the cache from the state store > > *How to reproduce* > # Suppose we have a ns ns60, which contains 2 nn, nn6001 is active and > nn6002 is standby > # Assuming that nn6001 and nn6002 are both in standby state, the priority of > nn6002 is higher than nn6001 > # Use default configuration > # Shutdown 2 nn's zkfs, {*}hadoop-daemon.sh stop zkfc{*}, manually perform > failover > # Manually switch nn6001 active->standby, *hdfs haadmin -ns ns60 > -transitionToStandby --forcemanual nn6001* > # Make sure that the NamenodeHeartbeatService reports that nn6001 is standby > !image-2023-08-26-11-48-22-131.png|width=800,height=20! > # Manually switch nn6001 active->standby, *hdfs haadmin -ns ns60 > -transitionToActive --forcemanual nn6001* > # The client accesses ns60 through router > !image-2023-08-26-11-56-50-181.png|width=800,height=50! > # After about one minute, request ns60 again through the router > !image-2023-08-26-11-59-25-153.png|width=800,height=50! > # Exceptions are reported for both requests, check the router log > !image-2023-08-26-12-01-39-968.png|width=800,height=20! > # The router cannot respond to the client's request for ns60 for a minute > > > *Fix the bug* > When an ns in the router's cache does not have an active nn, but in reality, > the ns has an active nn, and the client requests to throw a > NoNamenodesAvailableException, it is proven that the requested nn is a real > standby nn. The priority of this nn should be lowered so that the next > request will find the real active nn, avoiding constantly requesting the real > standby nn, which will cause the cache to be updated before the next time, > The router is unable to provide services for the ns to the client. > > *Test my patch* > *1. Unit testing* > *2. Comparison test* > * Suppose we have 2 clients [c1 c2], 2 routers [r1 r2] and a ns [ns60], the > ns has 2 nn [nn6001 nn6002] > * If both nn6001 and nn6002 are in standby state, the priority of nn6002 is > higher than nn6001, > * r1 uses the package that fixing the bug, r2 uses the original package > which has the bug > * c1 loops to send requests to r1, and c2 loops to send requests to r2, the > request is related to ns60 > * Make both nn6001 and nn6002 in standby state > * After the router reports that nn is in standby state, switch nn6001 to > active > *14:15:24* nn6001 is active > !image-2023-08-26-22-45-46-814.png|width=800,height=120! > * Check the log of router r1, after nn6001 switches to active, only > NoNamenodesAvailableException is printed once > !image-2023-08-26-22-47-22-276.png|width=800,height=30! > > * Check the log of router r2, and print NoNamenodesAvailableException for > more than one minute after nn6001 switches to active > !image-2023-08-26-22-47-41-988.png|width=800,height=150! > > * At 14:16:25, the client c2 accessing the router with the bug could not get > the data, and the client c1 accessing the router after the bug was fixed > could get the data normally: > c2's log:unable to access normally > !image-2023-08-26-22-48-02-086.png|width=800,height=50! > c1's log:display the result correctly > !image-2023-08-26-22-48-12-352.png|width=800,height=150! -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org