This site contains release notes for MapR Version 5.0 and below.  You can also refer to the release notes for the latest release.

Skip to end of metadata
Go to start of metadata

New In This Release

Resolved Issues


  • (Issue 9017) Multi-thread timing issue no longer results in null pointer exceptions.
  • (Issue 9044) Multi-thread issue timing issue with the Fair Scheduler no longer results in null pointer exceptions.
  • (Issue 9046) The script now uses a default path when mapred-site.xml does not specify the path.
  • (Issue 9075) The hadoop conf CLI tool checks key values and can dump the entire configuration.


  • (Issue 9067) JobTrackers start correctly after a manual rolling upgrade to this version.


  • (Issue 9080) The script now correctly invokes mrconfig.


  • (Issue 9037) MapReduce task attempts connect more reliably to the HBase Regionserver. Improved performance in fileclient, particularly in HBase random read operations.

Known Issues

(Issue 7310)

In some cases, Map/Reduce preemption may not work with Map Task prefetch and Expresslane. MapR recommends using prefetch, preemption and expresslane mutually exclusively.

(Issue 7332)

The bug is not yet fixed in MapR's release. It may cause the dropping of a table with a large number of partitions to fail due to an out-of-memory error.

(Issue 7834)

There are no obvious indications when a MapR license expires, except the degradation of services to the non-licensed level. The workaround is to pay attention to License expiration alarms before the actual expiry.

(Issue 10598)

When a node's IP number is reassigned to another node, remote procedure calls are misdirected to the wrong node. This can result in widespread errors affecting any system that use the RPC binding layer, including container resync operations that never finish or the creation of several superfluous containers. Restart the cluster to clear this condition.

(Issue 11389)

If you use the latest version of any browser to view the MCS, the CLDB, HBase, JobTracker, and job log pages do not load when you click on the respective links. As a workaround, use the following instructions to disable mixed-content-blocking in your browser:
Internet Explorer
Scroll to the bottom of the screen, and click Show all content. The page refreshes and displays mixed content. 

Mozilla Firefox

  1. At the top of the page, to the left of the address bar, click  (the shield icon).
  2. In the pop-up window that appears, click the down arrow next to "Keep Blocking", and select Disable Protection on This Page. The page refreshes and displays mixed content. The shield icon is replaced with a warning symbol to indicate that the page is displaying both secure and non-secure items.

Google Chrome

  1. Click  (the shield icon) on the right side of the address bar.
  2. In the icon dialog box, click Load anyway. The page refreshes and displays mixed content. The URL in the address bar shows https crossed out to indicate that the page is displaying both secure and non-secure items.

Map/Reduce and Hadoop Patches Integrated Since Last Release

The 2.1.1 release of the MapR distribution of Hadoop has not integrated any Apache Hadoop patches that are not included in the 2.1.0 release of the MapR distribution for Hadoop.

  • No labels