HDFS-3071. haadmin failover command does not provide enough detail when target NN is not ready to be active. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1304203 13f79535-47bb-0310-9956-ffa450edef68
Merge branch 'trunk' of https://github.com/apache/hadoop-common into trunk
HADOOP-8184.  ProtoBuf RPC engine uses the IPC layer reply packet.  Contributed by Sanjay Radia


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1304542 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-4043. Secret keys set in Credentials are not seen by tasks (Jason Lowe via bobby)


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1304587 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-7030. Add TableMapping topology implementation to read host to rack mapping from a file. Contributed by Patrick Angeles and tomwhite.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1304597 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-8163. Improve ActiveStandbyElector to provide hooks for fencing old active. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1304675 13f79535-47bb-0310-9956-ffa450edef68
HDFS-3132. Fix findbugs warning on HDFS trunk. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1304681 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-8193. Refactor FailoverController/HAAdmin code to add an abstract class for "target" services. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1304967 13f79535-47bb-0310-9956-ffa450edef68
HDFS-3116. Typo in fetchdt error message. Contributed by AOE Takashi.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1304996 13f79535-47bb-0310-9956-ffa450edef68
Revert HADOOP-8193 from r1304967. Patch introduced some NPEs in a test case.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1305152 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-8193. Refactor FailoverController/HAAdmin code to add an abstract class for "target" services. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1305195 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-8204. TestHealthMonitor fails occasionally. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1305199 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-3533. Add a channel between RM and AM to get information on nodes. Contributed by Bikas Saha. 


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Merge branch 'trunk' of https://github.com/apache/hadoop-common into trunk
MAPREDUCE-4066. Use default value when fetching MR_AM_STAGING_DIR. Contributed by xieguiming.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1305343 13f79535-47bb-0310-9956-ffa450edef68
HDFS-2941. Add an administrative command to download a copy of the fsimage from the NN. Contributed by Aaron T. Myers.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1305447 13f79535-47bb-0310-9956-ffa450edef68
Move CHANGES.txt entry for HDFS-2941 to the right version.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1305453 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-3353. Fixed commit msg to point to right jira.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1305457 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-8212. Improve ActiveStandbyElector's behavior when session expires. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1305510 13f79535-47bb-0310-9956-ffa450edef68
HDFS-3089. Move FSDatasetInterface and the related classes to a package.


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