the1plum...@gmail.com
Date: Tuesday, October 11, 2011 2:31 am
Subject: Re: Secondary namenode fsimage concept
To: common-user@hadoop.apache.org
hey parick
i wanted to configure my cluster to write namenode metadata to
multipledirectories as well:
property
hey parick
i wanted to configure my cluster to write namenode metadata to multiple
directories as well:
property
namedfs.name.dir/name
value/hadoop/var/name,/mnt/hadoop/var/name/value
/property
in my case, /hadoop/var/name is local directory, /mnt/hadoop/var/name is NFS
volume. i
: Shouguo Li the1plum...@gmail.com
Date: Tuesday, October 11, 2011 2:31 am
Subject: Re: Secondary namenode fsimage concept
To: common-user@hadoop.apache.org
hey parick
i wanted to configure my cluster to write namenode metadata to
multipledirectories as well:
property
namedfs.name.dir
:31 am
Subject: Re: Secondary namenode fsimage concept
To: common-user@hadoop.apache.org
hey parick
i wanted to configure my cluster to write namenode metadata to
multipledirectories as well:
property
namedfs.name.dir/name
value/hadoop/var/name,/mnt/hadoop/var/name/value
/property
Hi,
you're correct when saying the namenode hosts the fsimage file and the edits
log file.
The fsimage file contains a snapshot of the HDFS metadata (a filename to blocks
list mapping). Whenever there is a change to HDFS, it will be appended to the
edits file. Think of it as a database
Hi Kai,
In the Second part I meant
Is the secondary namenode also contain the FSImage file or the two
files(FSImage and EdiltLog) are transferred from the namenode at the checkpoint
time.
Thanks
Shanmuganathan
On Thu, 06 Oct 2011 11:37:50 +0530 Kai Voigtlt;k...@123.orggt;
Hi,
the secondary namenode only fetches the two files when a checkpointing is
needed.
Kai
Am 06.10.2011 um 08:45 schrieb shanmuganathan.r:
Hi Kai,
In the Second part I meant
Is the secondary namenode also contain the FSImage file or the two
files(FSImage and EdiltLog) are
Hi Kai,
There is no datas stored in the secondarynamenode related to the Hadoop
cluster . Am I correct?
If it correct means If we run the secondaryname node in separate machine then
fetching , merging and transferring time is increased if the cluster has large
data in the namenode
Hi,
yes, the secondary namenode is actually a badly named piece of software, as
it's not a namenode at all. And it's going to be renamed to checkpoint node.
To prevent metadata loss when your namenode fails, you should write the
namenode files to a local RAID and also a networked storage (NFS,
I would say your namenode write metadata in local fs (where your secondary
namenode will pull files), and NFS mount.
property
namedfs.name.dir/name
value/hadoop/name,/hadoop/nfs_server_name/value
/property
my 0.02$
P
On Thu, Oct 6, 2011 at 12:04 AM, shanmuganathan.r
Hi All,
I have a doubt in hadoop secondary namenode concept . Please
correct if the following statements are wrong .
The namenode hosts the fsimage and edit log files. The secondary namenode hosts
the fsimage file only. At the time of checkpoint the edit log file is
transferred
11 matches
Mail list logo