On Tue, Sep 29, 2009 at 5:17 AM, Stas Oskin <stas.os...@gmail.com> wrote: > Hi. > > Question - will DataNode ever try to format again the directory after the > initial format? > > Common sense says no, so if I erased them once and they ever come back, it > should not impact DataNode in any way? > > Thanks again. > > 2009/9/29 Anthony Urso <anthony.u...@gmail.com> > >> Those are created by fsck and will come back. They belong to the >> filesystem and you shouldn't delete them. >> >> Instead, create subdirectories on those mount points and use them as >> DFS directories. E.g. create and use /mnt/dfs instead of /mnt >> >> Cheers, >> Anthony >> >> On Mon, Sep 28, 2009 at 6:33 PM, Stas Oskin <stas.os...@gmail.com> wrote: >> > Hi. >> > >> > I'm trying to spread DataNode files over separate block devices, but >> these >> > have lost+found directories created. >> > >> > DataNode initialization fails because it can't erase them (probably >> because >> > it running under hadoop account). >> > >> > Any idea how to solve this? I can erase them manually, but what if they >> > appear again in future? >> > >> > Thanks. >> > >> >
The DataNode does not format. "hadoop namenode -format" formats the storage on the name node. The Datanode conducts blockreports and compares those to the namenode metadata and deletes unneeded blocks.
