Append Algorithm

[Wasim Bari <wa...@msn.com>]

Hadoop Append (0.19) works in same way as GFS does? 

GFS algorithm is below:

Application originates record append request.

2. GFS client translates request and sends it to master.

3. Master responds with chunk handle and (primary +

secondary) replica locations.

4. Client pushes write data to all locations.

Primary checks if record fits in specified chunk.

6. If record does not fit, then the primary:

. pads the chunk,

. tells secondaries to do the same,

. and informs the client.

. Client then retries the append with the nextchunk.

7. If record fits, then the primary:

. appends the record,

. tells secondaries to do the same,

. receives responses from secondaries,

. and sends final response to the client.

 

Re: how to re add a node

[Aaron Kimball <aa...@cloudera.com>]

ssh in, run:
cd $HADOOP_HOME
bin/hadoop-daemon.sh start tasktracker
bin/hadoop-daemon.sh start datanode

Similarly, to stop services on an individual machine, use
'bin/hadoop-daemon.sh stop servicename'
- Aaron

On Tue, Dec 9, 2008 at 2:15 PM, Elia Mazzawi
<el...@casalemedia.com>wrote:

> one of the nodes on my cluster had a power problem, now its back online how
> do i re add it into the cluster?
>
> we should add the answer to the FAQ,
> http://wiki.apache.org/hadoop/FAQ
>

how to re add a node

[Elia Mazzawi <el...@casalemedia.com>]

one of the nodes on my cluster had a power problem, now its back online 
how do i re add it into the cluster?

we should add the answer to the FAQ,
http://wiki.apache.org/hadoop/FAQ