#1608 amf: Support N_WAY model for admin operations on node group.

[Praveen]

Currently AMF supports 2N, NoRed and Nway_active models for
1)shutdown,
2) lock,
3) lock-in and
4) unlock-in
operations on nodegroup.
This ticket is for supporting N_WAY model for above mentioned operations on Node Group.

Note: SI deps will not be honored, within SU, while giving quiesced/quiescing assigments.

[Praveen]

High Level Changes at AMFD:
-Currently nodegroup.cc contains all checks related to validityof admin operation on NG hosting SU of a given red model. These checks are applicable to sg of N-Way model also. There is almost no change in this file except the removal of check on red model.
-After checking validity of lock and shutdown operation, AMFD calls SG FSM function for assignment handling for each SU hosted on a given node from NG's node list. Thus a new function ng_admin() is added in sg_nway_fsm.cc. This new function works at su level. Depending upon the HA state of SU, assignment message is sent to the Node director that hosts this SU. If SU has active state then quiescing or quiesced HA state is sent respectively for shutdown and lock operation. If SU has standby HA state then removal is sent for both shutdown and lock operations. SG is moved to REALIGN state. Upon receiving successful response for quiescing or quiesced assignements, AMFD tries to switchover each SUSI of this SU by making its peer SUSI active if they are not assigned on nodes of this nodegroup. If switchover is not possbile then AMFD sends removal of assignment to Node director hosting this quiescing/quiesced SU. After successful removal, SUSI are deleted at AMFD. In case of shutdown admin op, initial admin state of NG and Node will be SHUTTING_DOWN. When all the SUs of a node moves to quiesced state then Node transitions to LOCKED state. A NG transitions to LOCKED state when all its nodes transitions to LOCKED state. Admin operation finishes when all assignments gets removed in each SU hosted on nodes of NG. Since SG is moved to REALIGN state, any faults occured during assignment is handled by re-using red-model specific fault related code functions.
-For lock-in and unlock-in admin operations, there are no new changes execpt the removal of check on red models. In case of unlock-in operation, SUs are instantiated honoring PrefInserviceSU criteria.
-For unlock operations, SUs are assigned based on their ranks in SG on the nodes of NG. This is currenlty done by calling su_insvc() function from nodegroup.cc. There are also no changes in this area execpt removal of red model check.

Note: There are no changes at AMFND and AMFA.

[Praveen]

Issues reported in #1942 and #1944 are applicable to node group operations also. I wll be fixing them post FC tag.

[Praveen]

changeset: 7965:ccb2b870a5a0
tag: tip
user: praveen.malviya@oracle.com
date: Mon Aug 29 14:27:49 2016 +0530
summary: amfd: support N-Way model for supported admin ops on NG [#1608]

[Praveen]

Added Readme based on Minh's comment in changeset:

changeset: 7970:4bbc1bd1ef8d
user: praveen.malviya@oracle.com
date: Mon Aug 29 17:40:56 2016 +0530
summary: amfd: add README_NODEGROUP for nodegroup implementation [#1454, #1608]