configuration parameter to prevent accidental formatting of HDFS filesystem

Key: HDFS-718
URL: https://issues.apache.org/jira/browse/HDFS-718
Project: Hadoop HDFS
Issue Type: Improvement
Components: name-node
Affects Versions: 0.22.0
Environment: Any
Reporter: Andrew Ryan
Priority: Minor

Currently, any time the NameNode is not running, an HDFS filesystem will accept the 'format' command, and will duly format itself. There are those of us who have multi-PB HDFS filesystems who are really quite uncomfortable with this behavior. There is "Y/N" confirmation in the format command, but if the formatter genuinely believes themselves to be doing the right thing, the filesystem will be formatted.

This patch adds a configuration parameter to the namenode, dfs.namenode.support.allowformat, which defaults to "true," the current behavior: always allow formatting if the NameNode is down or some other process is not holding the namenode lock. But if dfs.namenode.support.allowformat is set to "false," the NameNode will not allow itself to be formatted until this config parameter is changed to "true".

The general idea is that for production HDFS filesystems, the user would format the HDFS once, then set dfs.namenode.support.allowformat to "false" for all time.

The attached patch was generated against trunk and +1's on my test machine. We have a 0.20 version that we are using in our cluster as well.

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

Search Discussions

Related Discussions

Discussion Navigation
viewthread | post
Discussion Overview
grouphdfs-dev @
postedOct 20, '09 at 10:46p
activeOct 20, '09 at 10:46p

1 user in discussion

Andrew Ryan (JIRA): 1 post



site design / logo © 2022 Grokbase