java7 is absent on Ubuntu Xenial and Hadoop 2.7.x+ is expected to work
on java8. So, use java8 on Ubuntu Xenial and java7 on old Ubuntu Trusty.
Change-Id: I64338c5c146e548f1b1ba2b1b1f1d5f76992b8e0
1. use ~/ instead of $DEST/
2. use "__slashplaceholder__" instead of @
3. add changed PATH to the first line of ~/.bashrc
3. Fix the auto exit issue in start_hdfs.sh, make sure all hdfs services start
4. Add test_hdfs method after hdfs start
Change-Id: I82a70d67209f27edead50d64dea03e5cb5ce925a
If we run ./unstack.sh more than once, issues will happen:
1. stop-dfs.sh do not exist
2. ~/.bashrc will be emptied due to $line is empty
Change-Id: Iaa058a33ddf7fe4366ffc6c7ea4e408d6b267967