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diff --git a/docs/development/manuals/get-valid-server-state.rst b/docs/development/manuals/get-valid-server-state.rst deleted file mode 100644 index 824ea3c2..00000000 --- a/docs/development/manuals/get-valid-server-state.rst +++ /dev/null @@ -1,125 +0,0 @@ -.. This work is licensed under a Creative Commons Attribution 4.0 International License. -.. http://creativecommons.org/licenses/by/4.0 - -====================== -Get valid server state -====================== - -Related Blueprints: -=================== - -https://blueprints.launchpad.net/nova/+spec/get-valid-server-state - -Problem description -=================== - -Previously when the owner of a VM has queried his VMs, he has not received -enough state information, states have not changed fast enough in the VIM and -they have not been accurate in some scenarios. With this change this gap is now -closed. - -A typical case is that, in case of a fault of a host, the user of a high -availability service running on top of that host, needs to make an immediate -switch over from the faulty host to an active standby host. Now, if the compute -host is forced down [1] as a result of that fault, the user has to be notified -about this state change such that the user can react accordingly. Similarly, -a change of the host state to "maintenance" should also be notified to the -users. - -What is changed -=============== - -A new ``host_status`` parameter is added to the ``/servers/{server_id}`` and -``/servers/detail`` endpoints in microversion 2.16. By this new parameter -user can get additional state information about the host. - -``host_status`` possible values where next value in list can override the -previous: - -- ``UP`` if nova-compute is up. -- ``UNKNOWN`` if nova-compute status was not reported by servicegroup driver - within configured time period. Default is within 60 seconds, - but can be changed with ``service_down_time`` in nova.conf. -- ``DOWN`` if nova-compute was forced down. -- ``MAINTENANCE`` if nova-compute was disabled. MAINTENANCE in API directly - means nova-compute service is disabled. Different wording is used to avoid - the impression that the whole host is down, as only scheduling of new VMs - is disabled. -- Empty string indicates there is no host for server. - -``host_status`` is returned in the response in case the policy permits. By -default the policy is for admin only in Nova policy.json:: - - "os_compute_api:servers:show:host_status": "rule:admin_api" - -For an NFV use case this has to also be enabled for the owner of the VM:: - - "os_compute_api:servers:show:host_status": "rule:admin_or_owner" - -REST API examples: -================== - -Case where nova-compute is enabled and reporting normally:: - - GET /v2.1/{tenant_id}/servers/{server_id} - - 200 OK - { - "server": { - "host_status": "UP", - ... - } - } - -Case where nova-compute is enabled, but not reporting normally:: - - GET /v2.1/{tenant_id}/servers/{server_id} - - 200 OK - { - "server": { - "host_status": "UNKNOWN", - ... - } - } - -Case where nova-compute is enabled, but forced_down:: - - GET /v2.1/{tenant_id}/servers/{server_id} - - 200 OK - { - "server": { - "host_status": "DOWN", - ... - } - } - -Case where nova-compute is disabled:: - - GET /v2.1/{tenant_id}/servers/{server_id} - - 200 OK - { - "server": { - "host_status": "MAINTENANCE", - ... - } - } - -Host Status is also visible in python-novaclient:: - - +-------+------+--------+------------+-------------+----------+-------------+ - | ID | Name | Status | Task State | Power State | Networks | Host Status | - +-------+------+--------+------------+-------------+----------+-------------+ - | 9a... | vm1 | ACTIVE | - | RUNNING | xnet=... | UP | - +-------+------+--------+------------+-------------+----------+-------------+ - -Links: -====== - -[1] Manual for OpenStack NOVA API for marking host down -http://artifacts.opnfv.org/doctor/docs/manuals/mark-host-down_manual.html - -[2] OpenStack compute manual page -http://developer.openstack.org/api-ref-compute-v2.1.html#compute-v2.1 |