From 057c92fe066c2debec7aa568113922a433b56a26 Mon Sep 17 00:00:00 2001 From: Christian Berendt Date: Thu, 2 Jun 2016 15:49:15 +0200 Subject: [PATCH] Document the use of external Ceph journal drives Change-Id: I3f0873f425f49514e6f086a6baa25dc3a3ee1dd5 Closes-bug: #1560049 --- doc/ceph-guide.rst | 50 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 48 insertions(+), 2 deletions(-) diff --git a/doc/ceph-guide.rst b/doc/ceph-guide.rst index 1f892e13ba..2be412ae52 100644 --- a/doc/ceph-guide.rst +++ b/doc/ceph-guide.rst @@ -15,8 +15,8 @@ Requirements * A minimum of 3 hosts for a vanilla deploy * A minimum of 1 block device per host -Preparation and Deployment -========================== +Preparation +=========== To prepare a disk for use as a `Ceph OSD `_ you must add a @@ -47,6 +47,49 @@ usage with Kolla. 1 1049kB 10.7GB 10.7GB KOLLA_CEPH_OSD_BOOTSTRAP +Using an external journal drive +------------------------------- + +The steps documented above created a journal partition of 5 GByte +and a data partition with the remaining storage capacity on the same tagged +drive. + +It is a common practice to place the journal of an OSD on a separate +journal drive. This section documents how to use an external journal drive. + +Prepare the storage drive in the same way as documented above: + +:: + + # + # where $DISK is /dev/sdb or something similar + parted $DISK -s -- mklabel gpt mkpart KOLLA_CEPH_OSD_BOOTSTRAP_FOO 1 -1 + +To prepare the journal external drive execute the following command: + +:: + + # + # where $DISK is /dev/sdc or something similar + parted $DISK -s -- mklabel gpt mkpart KOLLA_CEPH_OSD_BOOTSTRAP_FOO_J 1 -1 + +.. note:: + + Use different suffixes (``_42``, ``_FOO``, ``_FOO42``, ..) to use different external + journal drives for different storage drives. One external journal drive can only + be used for one storage drive. + +.. note:: + + The partition labels ``KOLLA_CEPH_OSD_BOOTSTRAP`` and ``KOLLA_CEPH_OSD_BOOTSTRAP_J`` + are not working when using external journal drives. It is required to use + suffixes (``_42``, ``_FOO``, ``_FOO42``, ..). If you want to setup only one + storage drive with one external journal drive it is also necessary to use a suffix. + + +Configuration +============= + Edit the [storage] group in the inventory which contains the hostname of the hosts that have the block devices you have prepped as shown above. @@ -82,6 +125,9 @@ and add the contents:: osd pool default min size = 1 +Deployment +========== + Finally deploy the Ceph-enabled OpenStack: ::