Qemu COLO Fault Tolerance
=========================
-| Copyright (c) 2016 Intel Corporation
-| Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
-| Copyright (c) 2016 Fujitsu, Corp.
-
This document gives an overview of COLO's design and how to use it.
Background
| Storage | |External Network| | External Network | | Storage |
+---------------+ +----------------+ +------------------+ +--------------+
-Components introduction
-^^^^^^^^^^^^^^^^^^^^^^^
+Components
+^^^^^^^^^^
You can see there are several components in COLO's diagram of architecture.
Their functions are described below.
Test procedure
--------------
-Note: Here we are running both instances on the same host for testing,
+
+Setup
+^^^^^
+
+Here we are running both instances on the same host for testing,
change the IP Addresses if you want to run it on two hosts. Initially
``127.0.0.1`` is the Primary Host and ``127.0.0.2`` is the Secondary Host.
+COLO uses double the guest ram size on the secondary side. The Qemu version
+should be the same on both hosts.
+
Startup qemu
^^^^^^^^^^^^
**1. Primary**:
-Note: Initially, ``$imagefolder/primary.qcow2`` needs to be copied to all hosts.
+Initially, ``$imagefolder/primary.qcow2`` needs to be copied to all hosts.
You don't need to change any IP's here, because ``0.0.0.0`` listens on any
interface. The chardev's with ``127.0.0.1`` IP's loopback to the local qemu
instance::
**2. Secondary**:
-Note: Active and hidden images need to be created only once and the
+Active and hidden images need to be created only once and the
size should be the same as ``primary.qcow2``. Again, you don't need to change
any IP's here, except for the ``$primary_ip`` variable::
{"execute": "migrate-set-capabilities", "arguments":{ "capabilities": [ {"capability": "x-colo", "state": true } ] } }
{"execute": "migrate", "arguments":{ "uri": "tcp:127.0.0.1:9998" } }
-TODO
-----
-1. Support shared storage.
-2. Develop the heartbeat part.
-3. Reduce checkpoint VM’s downtime while doing checkpoint.
+| Copyright (c) 2016 Intel Corporation
+| Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
+| Copyright (c) 2016 Fujitsu, Corp.