Re: Hadoop ReInitialization.

2009-06-03 Thread Aaron Kimball
You can block for safemode exit by running 'hadoop dfsadmin -safemode wait'
rather than sleeping for an arbitrary amount of time.

More generally, I'm a bit confused what you mean by all this. Hadoop daemons
may individually crash, but you should never need to reformat HDFS and start
from scratch. If you're doing this, that means that you're probably sticking
some important hadoop files in a temp dir that's getting cleaned out or
something of the like. Are dfs.data.dir and dfs.name.dir suitably
well-protected from tmpwatch or other such "housekeeping" programs?

- Aaron

On Wed, Jun 3, 2009 at 4:50 AM, Steve Loughran  wrote:

> b wrote:
>
>  But after formatting and starting DFS i need to wait some time (sleep 60)
>> before putting data into HDFS. Else i will receive
>> "NotReplicatedYetException".
>>
>
> that means the namenode is up but there aren't enough workers yet.
>


Re: Hadoop ReInitialization.

2009-06-03 Thread Steve Loughran

b wrote:

But after formatting and starting DFS i need to wait some time (sleep 
60) before putting data into HDFS. Else i will receive 
"NotReplicatedYetException".


that means the namenode is up but there aren't enough workers yet.


Hadoop ReInitialization.

2009-06-03 Thread b


Hello all.

I need to process many Gigs of new data each 10 minutes. Each 10 minutes  
cron launches bash script "do.sh" that puts data into HDFS and launches  
processing. But...


Hadoop isn't military software, so there is probability of errors with  
HDFS. So i need to watch LOG files to catch problems. For example, HDFS  
may crash and it will be need to format whole HDFS, delete /tmp/hadoop*,  
ets...


So i decided to do full restart each 10 mins whole cluster before begining  
of data processing. I am erasing all /tmp/hadoop* on each node by ssh,  
start dfs, start mapred, put binaries and data and then run processing.


But after formatting and starting DFS i need to wait some time (sleep 60)  
before putting data into HDFS. Else i will receive  
"NotReplicatedYetException".


What you think about this all? Thank you :)