From 9dcb598cd07b8417ef7351999348b34eb43f50e6 Mon Sep 17 00:00:00 2001 From: John Garbutt Date: Wed, 25 Nov 2015 12:22:37 +0000 Subject: [PATCH] docs: reorder move servers text I have moved the resize and shelved operations after the discussion of the cloud operator initiated migrate. This adds better context around the comments that say resize and shelved are unlikely to be initiated by and operator. blueprint complete-todo-in-api-concept-doc Change-Id: I7fd72b5fd2d4e724d4465fe002f7951e60dcbe3d --- api-guide/source/server_concepts.rst | 114 +++++++++++++-------------- 1 file changed, 57 insertions(+), 57 deletions(-) diff --git a/api-guide/source/server_concepts.rst b/api-guide/source/server_concepts.rst index e426fc9d56..0be7d63acc 100644 --- a/api-guide/source/server_concepts.rst +++ b/api-guide/source/server_concepts.rst @@ -399,63 +399,6 @@ compute host to another including shelve, resize, migrations and evacuate. The following use cases demonstrate the intention of the actions and the consequence for operational procedures. -User doesn't want to be charged when not using a server -------------------------------------------------------- - -Sometimes a user does not require a server to be active for a while, -perhaps over a weekend or at certain times of day. -Ideally they don't want to be billed for those resources. -Just powering down a server does not free up any resources, -but shelving a server does free up resources to be used by other users. -This makes it feasible for a cloud operator to offer a discount when -an server is shelved. - -When the user shelves a server the operator can choose to remove it -from the compute hosts, i.e. the operator can offload the shelved server. -When the user's server is unshelved, it is scheduled to a new -host according to the operators policies for distributing work loads -across the compute hosts, including taking disabled hosts into account. -This will contribute to increased overall capacity, freeing hosts that -are ear-marked for maintenance and providing contiguous blocks -of resources on single hosts due to moving out old servers. - -Shelving a server is not normally a choice that is available to -the cloud operator because it affects the availability of the server -being provided to the user. - -User resizes server to get more resources ------------------------------------------ - -Sometimes a user may want to change the flavor of a server, e.g. change -the quantity of cpus, disk, memory or any other resource. This is done -by rebuilding the server with a new flavor. As the server is being -moved, it is normal to reschedule the server to another host -(although resize to the same host is an option for the operator). - -Resize involves shutting down the server, finding a host that has -the correct resources for the new flavor size, moving the current -server (including all storage) to the new host. Once the server -has been given the appropriate resources to match the new flavor, -the server is started again. - -After the resize operation, when the user is happy their server is -working correctly after the resize, the user calls Confirm Resize. -This deletes the backup server that was kept on the source host. -Alternatively, the user can call Revert Resize to delete the new -resized server, and restore the back up that was stored on the source -host. If the user does not manually confirm the resize within a -configured time period, the resize is automatically confirmed, to -free up the space the backup is using on the source host. - -As with shelving, resize provides the cloud operator with an -opportunity to redistribute work loads across the cloud according -to the operators scheduling policy, providing the same benefits as -above. - -Resizing a server is not normally a choice that is available to -the cloud operator because it changes the nature of the server -being provided to the user. - Cloud operator needs to move a server ------------------------------------- @@ -564,3 +507,60 @@ Evacuating a server is solely in the domain of the cloud operator because it must be performed in coordination with other operational procedures to be safe. A user is not normally aware of compute hosts but is adversely affected by their failure. + +User resizes server to get more resources +----------------------------------------- + +Sometimes a user may want to change the flavor of a server, e.g. change +the quantity of cpus, disk, memory or any other resource. This is done +by rebuilding the server with a new flavor. As the server is being +moved, it is normal to reschedule the server to another host +(although resize to the same host is an option for the operator). + +Resize involves shutting down the server, finding a host that has +the correct resources for the new flavor size, moving the current +server (including all storage) to the new host. Once the server +has been given the appropriate resources to match the new flavor, +the server is started again. + +After the resize operation, when the user is happy their server is +working correctly after the resize, the user calls Confirm Resize. +This deletes the backup server that was kept on the source host. +Alternatively, the user can call Revert Resize to delete the new +resized server, and restore the back up that was stored on the source +host. If the user does not manually confirm the resize within a +configured time period, the resize is automatically confirmed, to +free up the space the backup is using on the source host. + +As with shelving, resize provides the cloud operator with an +opportunity to redistribute work loads across the cloud according +to the operators scheduling policy, providing the same benefits as +above. + +Resizing a server is not normally a choice that is available to +the cloud operator because it changes the nature of the server +being provided to the user. + +User doesn't want to be charged when not using a server +------------------------------------------------------- + +Sometimes a user does not require a server to be active for a while, +perhaps over a weekend or at certain times of day. +Ideally they don't want to be billed for those resources. +Just powering down a server does not free up any resources, +but shelving a server does free up resources to be used by other users. +This makes it feasible for a cloud operator to offer a discount when +an server is shelved. + +When the user shelves a server the operator can choose to remove it +from the compute hosts, i.e. the operator can offload the shelved server. +When the user's server is unshelved, it is scheduled to a new +host according to the operators policies for distributing work loads +across the compute hosts, including taking disabled hosts into account. +This will contribute to increased overall capacity, freeing hosts that +are ear-marked for maintenance and providing contiguous blocks +of resources on single hosts due to moving out old servers. + +Shelving a server is not normally a choice that is available to +the cloud operator because it affects the availability of the server +being provided to the user.