Hi. You mean, you couldn't recover the NameNode from checkpoints because of timestamps?
Regards. On Tue, Oct 27, 2009 at 4:49 PM, Jason Venner <jason.had...@gmail.com>wrote: > 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 >
