diff options
Diffstat (limited to 'requirements/02-use_cases.rst')
| -rw-r--r-- | requirements/02-use_cases.rst | 30 |
1 files changed, 14 insertions, 16 deletions
diff --git a/requirements/02-use_cases.rst b/requirements/02-use_cases.rst index f69151df..775f0b77 100644 --- a/requirements/02-use_cases.rst +++ b/requirements/02-use_cases.rst @@ -48,7 +48,7 @@ Faults Fault management using ACT-STBY configuration ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -In :num:`Figure #figure1`, a system-wide view of relevant functional blocks is +In :numref:`figure1`, a system-wide view of relevant functional blocks is presented. OpenStack is considered as the VIM implementation (aka Controller) which has interfaces with the NFVI and the Consumers. The VNF implementation is represented as different virtual resources marked by different colors. Consumers @@ -56,7 +56,7 @@ represented as different virtual resources marked by different colors. Consumers resources (VMs in this example) shown with the same colors. The first requirement in this use case is that the Controller needs to detect -faults in the NVFI ("1. Fault Notification" in :num:`Figure #figure1`) affecting +faults in the NVFI ("1. Fault Notification" in :numref:`figure1`) affecting the proper functioning of the virtual resources (labelled as VM-x) running on top of it. It should be possible to configure which relevant fault items should be detected. The VIM (e.g. OpenStack) itself could be extended to detect such @@ -66,21 +66,20 @@ element can be considered as a component of VIM from an architectural point of view. Once such fault is detected, the VIM shall find out which virtual resources are -affected by this fault. In the example in :num:`Figure #figure1`, VM-4 is +affected by this fault. In the example in :numref:`figure1`, VM-4 is affected by a fault in the Hardware Server-3. Such mapping shall be maintained in the VIM, depicted as the "Server-VM info" table inside the VIM. Once the VIM has identified which virtual resources are affected by the fault, it needs to find out who is the Consumer (i.e. the owner/manager) of the -affected virtual resources (Step 2). In the example shown in :num:`Figure -#figure1`, the VIM knows that for the red VM-4, the manager is the red Consumer +affected virtual resources (Step 2). In the example shown in :numref:`figure1`, +the VIM knows that for the red VM-4, the manager is the red Consumer through an Ownership info table. The VIM then notifies (Step 3 "Fault Notification") the red Consumer about this fault, preferably with sufficient abstraction rather than detailed physical fault information. -.. _figure1: - .. figure:: images/figure1.png + :name: figure1 :width: 100% Fault management/recovery use case @@ -96,7 +95,7 @@ components, minimizing Doctor's reaction time is a necessary basic ingredient to fast failover times in general. Once the Consumer has switched to STBY configuration, it notifies (Step 5 -"Instruction" in :num:`Figure #figure1`) the VIM. The VIM can then take +"Instruction" in :numref:`figure1`) the VIM. The VIM can then take necessary (e.g. pre-determined by the involved network operator) actions on how to clean up the fault affected VMs (Step 6 "Execute Instruction"). @@ -127,7 +126,7 @@ prediction in the VIM are investigated in the OPNFV project "Data Collection for Failure Prediction" [PRED]_. This use case is very similar to :ref:`uc-fault1`. Instead of a fault -detection (Step 1 "Fault Notification in" :num:`Figure #figure1`), the trigger +detection (Step 1 "Fault Notification in" :numref:`figure1`), the trigger comes from a fault prediction module in the VIM, or from a third party module which notifies the VIM about an imminent fault. From Step 2~5, the work flow is the same as in the "Fault management using ACT-STBY configuration" use case, @@ -163,11 +162,11 @@ mark them with an appropriate flag (i.e. "maintenance" state) such that these servers are not considered for hosting of virtual machines until the maintenance flag is cleared (i.e. nodes are back in "normal" status). -A high-level view of the maintenance procedure is presented in :num:`Figure -#figure2`. VIM/OpenStack, through its northbound interface, receives a -maintenance notification (Step 1 "Maintenance Request") from the Administrator -(e.g. a network operator) including information about which hardware is subject -to maintenance. Maintenance operations include replacement/upgrade of hardware, +A high-level view of the maintenance procedure is presented in :numref:`figure2`. +VIM/OpenStack, through its northbound interface, receives a maintenance notification +(Step 1 "Maintenance Request") from the Administrator (e.g. a network operator) +including information about which hardware is subject to maintenance. +Maintenance operations include replacement/upgrade of hardware, update/upgrade of the hypervisor/host OS, etc. The consequent steps to enable the Consumer to perform ACT-STBY switching are @@ -183,9 +182,8 @@ Hardware Servers so that consequent maintenance operations could be performed. Due to the similarity for Steps 2~6, the maintenance procedure and the fault management procedure are investigated in the same project. -.. _figure2: - .. figure:: images/figure2.png + :name: figure2 :width: 100% Maintenance use case |