We have been having some trouble with the secondary on a cluster that has one edit log partition on an nfs server, with the namenode rejecting the merged images due to timestamp missmatches.
On Mon, Oct 26, 2009 at 10:14 AM, Stas Oskin <stas.os...@gmail.com> wrote: > Hi. > > Thanks for the advice, it seems that the initial approach of having single > SecNameNode writing to exports is the way to go. > > By the way, I asked this already, but wanted to clarify: > > * It's possible to set how often SecNameNode checkpoints the data (what is > the setting by the way)? > > * It's possible to let NameNode write to exports as well together with > local > disk, which ensures the latest possible meta-data in case of disk crash > (compared to pereodic check-pointing), but it's going to slow down the > operations due to network read/writes. > > Thanks again. > > On Thu, Oct 22, 2009 at 10:03 PM, Patrick Angeles > <patrickange...@gmail.com>wrote: > > > From what I understand, it's rather tricky to set up multiple secondary > > namenodes. In either case, running multiple 2ndary NNs doesn't get you > > much. > > See this thread: > > http://www.mail-archive.com/core-u...@hadoop.apache.org/msg06280.html > > > > On Wed, Oct 21, 2009 at 10:44 AM, Stas Oskin <stas.os...@gmail.com> > wrote: > > > > > To clarify, it's either let single SecNameNode to write to multiple NFS > > > exports, or actually have multiple SecNameNodes. > > > > > > Thanks again. > > > > > > On Wed, Oct 21, 2009 at 4:43 PM, Stas Oskin <stas.os...@gmail.com> > > wrote: > > > > > > > Hi. > > > > > > > > I'm want to keep a checkpoint data on several separate machines for > > > backup, > > > > and deliberating between exporting these machines disks via NFS, or > > > actually > > > > running Secondary Name Nodes there. > > > > > > > > Can anyone advice what would be better in my case? > > > > > > > > Regards. > > > > > > > > > > -- Pro Hadoop, a book to guide you from beginner to hadoop mastery, http://www.amazon.com/dp/1430219424?tag=jewlerymall www.prohadoopbook.com a community for Hadoop Professionals
