From: Sage Weil Date: Fri, 15 Apr 2016 18:49:40 +0000 (-0400) Subject: doc/release-notes: more detail about the ext4 checks X-Git-Tag: v10.2.0~6^2~3 X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=b2d9467ff3c202a16b7b1ecfa2a76b9deef17092;p=ceph.git doc/release-notes: more detail about the ext4 checks Signed-off-by: Sage Weil --- diff --git a/doc/release-notes.rst b/doc/release-notes.rst index 211d7eebde31..527801b45946 100644 --- a/doc/release-notes.rst +++ b/doc/release-notes.rst @@ -141,12 +141,29 @@ We now build packages for: Upgrading from Infernalis or Hammer ----------------------------------- -* We now recommend against using ``ext4`` as the underlying file system for - Ceph OSDs, especially when RGW or other users of long RADOS object names - are used. For more information, please see `Filesystem Recommendations`_. +* We now recommend against using ``ext4`` as the underlying file + system for Ceph OSDs, especially when RGW or other users of long + RADOS object names are used. For more information about why, please + see `Filesystem Recommendations`_. + + If you have an existing cluster that uses ext4 for the OSDs but uses only + RBD and/or CephFS, then the ext4 limitations will not affect you. Before + upgrading, be sure add the following to ``ceph.conf`` to allow the OSDs to + start:: + + osd max object name len = 256 + osd max object namespace len = 64 + + Keep in mind that if you set these lower object name limits and + later decide to use RGW on this cluster, it will have problems + storing S3/Swift objects with long names. This startup check can also be + disabled via the below option, although this is not recommended:: + + osd check max object name len on startup = false .. _Filesystem Recommendations: ../configuration/filesystem-recommendations + * There are no major compatibility changes since Infernalis. Simply upgrading the daemons on each host and restarting all daemons is sufficient.