Tachyon was not formatted!

When you are using HDFS as your underFSAddress, you may faced this error.

By inspecting master.log you can find out the error log as follows.

devan@Dev-ThinkPad-X230:~/tachyon-0.7.1$ tailf logs/master.log 

2015-12-18 10:14:34,571 ERROR MASTER_LOGGER (TachyonMaster.java:main) - Uncaught exception terminating Master
java.lang.IllegalStateException: Tachyon was not formatted! The journal folder is $TACHYON_HOME/journal/
at com.google.common.base.Preconditions.checkState(Preconditions.java:149)
at tachyon.master.TachyonMaster.<init>(TachyonMaster.java:151)
at tachyon.master.TachyonMaster.main(TachyonMaster.java:63)

Solution

You need to delete HDFS temporary files created by tachyon in your underFS HDFS server.

hadoop fs -rm -r /tmp/tachyon/

Note : Tachyon will create a directory structure as follows in underFS HDFS server,

/tmp/tachyon/data/1

/tmp/tachyon/data/2

....