Abstract: A computing system that receives and stores configuration information for the application in a data store. The configuration information comprises (1) identifiers for a plurality of cells of the application that include at least a primary cell and a secondary cell, (2) a defined state for each of the plurality of cells, (3) one or more dependencies for the application, and (4) a failover workflow defining actions to take in a failover event. The computing system receives an indication, from a customer, of a change in state of the primary cell or a request to initiate the failover event. The computing system updates, in the data store, the states for corresponding cells of the plurality of cells based on the failover workflow and updates, in the data store, the one or more dependencies for the application based on the failover workflow.

Abstract: a computing system that receives and stores configuration information for the application in a data store. The configuration information comprises (1) identifiers for a plurality of cells of the application that include at least a primary cell and a secondary cell, (2) a defined state for each of the plurality of cells, (3) one or more dependencies for the application, and (4) a failover workflow defining actions to take in a failover event. The computing system receives an indication, from a customer, of a change in state of the primary cell or a request to initiate the failover event. The computing system updates, in the data store, the states for corresponding cells of the plurality of cells based on the failover workflow and updates, in the data store, the one or more dependencies for the application based on the failover workflow.

Abstract: Techniques are described for providing service availability zones for computing-related services provided by a cloud provider network. According to some embodiments, the use of service availability zones enables users to achieve greater availability assurance for workloads sensitive to downtime or outages. The sensitivity of such workloads to downtime may be due to financial, regulatory, safety, or other reasons. Such availability-sensitive applications may in some cases be configured to run in multiple regions of a cloud provider network to increase their availability compared to running in a single availability zone. However, for some applications, the implementation of an application across multiple regions may not be feasible or desirable. The use of service availability zones provides user-visible fault domains within a single region of a cloud provider network, thereby enabling users to readily and reliably achieve application layer availability of approximately 99.

Abstract: The present disclosure generally relates to managing a failover service. The failover service can receive a list of regions and a list of rules that must be satisfied for a region to be considered available for failover. The failover service can then determine the regions that satisfy each rule of the list of rules and are available for failover. The failover service can then deliver this information to a client. The failover service can determine the regions that do not satisfy one or more of the rules from the list of rules and deliver this information to a client. The failover service can perform automatic remediation to the unavailable failover regions and client remediation to the unavailable failover regions.

Abstract: a computing system that receives and stores configuration information for the application in a data store. The configuration information comprises (1) identifiers for a plurality of cells of the application that include at least a primary cell and a secondary cell, (2) a defined state for each of the plurality of cells, (3) one or more dependencies for the application, and (4) a failover workflow defining actions to take in a failover event. The computing system receives an indication, from a customer, of a change in state of the primary cell or a request to initiate the failover event. The computing system updates, in the data store, the states for corresponding cells of the plurality of cells based on the failover workflow and updates, in the data store, the one or more dependencies for the application based on the failover workflow.

Abstract: The present disclosure generally relates to managing a failover service for regions in an active-active configuration. The failover service can receive a list of regions and a list of rules that must be satisfied for a region to be considered available for failover. For each primary region of a plurality of primary regions, the failover service can then determine the regions that satisfy each rule of the list of rules and are available for failover. The failover service can then deliver this information to a client. The failover service can determine the regions that do not satisfy one or more of the rules from the list of rules and deliver this information to a client. The failover service can perform automatic remediation and client remediation to the unavailable failover regions.

Abstract: The present disclosure generally relates to managing a failover service. The regional management service can receive a list of primary regions and a list of rules for each primary region that must be satisfied for a primary region to be considered available for failover from the respective primary region. The regional management service can then determine the primary regions that satisfy each rule of the list of rules for one or more primary regions and are available for failover of the respective primary regions. The regional management service can then deliver this information to a client. The regional management service can determine the primary regions that do not satisfy one or more of the rules from the list of rules for one or more primary regions and deliver this information to a client. The regional management service can perform automatic remediation and client remediation to the unavailable primary regions.

Abstract: The present disclosure generally relates to managing a failover service. The failover service can receive a list of regions and a list of rules that must be satisfied for a region to be considered available for failover. The failover service can then determine the regions that satisfy each rule of the list of rules and are available for failover. The failover service can then deliver this information to a client. The failover service can determine the regions that do not satisfy one or more of the rules from the list of rules and deliver this information to a client. The failover service can perform automatic remediation to the unavailable failover regions and client remediation to the unavailable failover regions.

Abstract: Systems and methods are disclosed to implement a real-time data validation system that prevents problematic updates from being replicated from a primary database to a replica database. In embodiments, the data validation system injects a time delay into the replication process, so that when an update in a replication stream fails a specified data validation, the data validation system will prevent the update from being applied to the replica. In embodiments, the replication process is halted, a snapshot of the replica database is taken during the halt, and replication to the replica is resumed. Accordingly, if the problematic update is later confirmed to be invalid, the replica database can be rolled back to a point before the problematic update. Advantageously, the disclosed system can be used to implement a variety of data validations on top of a database replication process to protect the replica database from receiving undesired updates.

Abstract: A computing system that receives and stores configuration information for the application in a data store. The configuration information comprises (1) identifiers for a plurality of cells of the application that include at least a primary cell and a secondary cell, (2) a defined state for each of the plurality of cells, (3) one or more dependencies for the application, and (4) a failover workflow defining actions to take in a failover event. The computing system receives an indication, from a customer, of a change in state of the primary cell or a request to initiate the failover event. The computing system updates, in the data store, the states for corresponding cells of the plurality of cells based on the failover workflow and updates, in the data store, the one or more dependencies for the application based on the failover workflow.

Abstract: a data store and a proxy system. The data store may store state data relating to a cell of the application, each cell having a state. The proxy system may identify whether the cell is operating in the active state, the passive state, or the fenced state and access a database of acceptable and unacceptable commands for the cell's state. For each request directed to the cell received, the proxy system may identifies the request as an acceptable request based on identifying that one or more commands of the request are acceptable to process in the cell's state or identifies the request as an unacceptable request based on identifying that one or more commands of the request are unacceptable to process in the cell's state. The proxy system then conveys the acceptable requests and unacceptable requests appropriately.

Abstract: Systems and methods are disclosed to implement a real-time data validation system that prevents problematic updates from being replicated from a primary database to a replica database. In embodiments, the data validation system injects a time delay into the replication process, so that when an update in a replication stream fails a specified data validation, the data validation system will prevent the update from being applied to the replica. In embodiments, the replication process is halted, a snapshot of the replica database is taken during the halt, and replication to the replica is resumed. Accordingly, if the problematic update is later confirmed to be invalid, the replica database can be rolled back to a point before the problematic update. Advantageously, the disclosed system can be used to implement a variety of data validations on top of a database replication process to protect the replica database from receiving undesired updates.

Abstract: The present disclosure generally relates to managing a failover service. The regional management service can receive a list of primary regions and a list of rules for each primary region that must be satisfied for a primary region to be considered available for failover from the respective primary region. The regional management service can then determine the primary regions that satisfy each rule of the list of rules for one or more primary regions and are available for failover of the respective primary regions. The regional management service can then deliver this information to a client. The regional management service can determine the primary regions that do not satisfy one or more of the rules from the list of rules for one or more primary regions and deliver this information to a client. The regional management service can perform automatic remediation and client remediation to the unavailable primary regions.

Abstract: The present disclosure generally relates to managing a failover service for regions in an active-active configuration. The failover service can receive a list of regions and a list of rules that must be satisfied for a region to be considered available for failover. For each primary region of a plurality of primary regions, the failover service can then determine the regions that satisfy each rule of the list of rules and are available for failover. The failover service can then deliver this information to a client. The failover service can determine the regions that do not satisfy one or more of the rules from the list of rules and deliver this information to a client. The failover service can perform automatic remediation and client remediation to the unavailable failover regions.

Abstract: The present disclosure generally relates to managing a failover service. The failover service can receive a list of regions and a list of rules that must be satisfied for a region to be considered available for failover. The failover service can then determine the regions that satisfy each rule of the list of rules and are available for failover. The failover service can then deliver this information to a client. The failover service can determine the regions that do not satisfy one or more of the rules from the list of rules and deliver this information to a client. The failover service can perform automatic remediation to the unavailable failover regions and client remediation to the unavailable failover regions.

Abstract: a data store and a proxy system. The data store may store state data relating to a cell of the application, each cell having a state. The proxy system may identify whether the cell is operating in the active state, the passive state, or the fenced state and access a database of acceptable and unacceptable commands for the cell's state. For each request directed to the cell received, the proxy system may identifies the request as an acceptable request based on identifying that one or more commands of the request are acceptable to process in the cell's state or identifies the request as an unacceptable request based on identifying that one or more commands of the request are unacceptable to process in the cell's state. The proxy system then conveys the acceptable requests and unacceptable requests appropriately.

Abstract: a computing system that receives and stores configuration information for the application in a data store. The configuration information comprises (1) identifiers for a plurality of cells of the application that include at least a primary cell and a secondary cell, (2) a defined state for each of the plurality of cells, (3) one or more dependencies for the application, and (4) a failover workflow defining actions to take in a failover event. The computing system receives an indication, from a customer, of a change in state of the primary cell or a request to initiate the failover event. The computing system updates, in the data store, the states for corresponding cells of the plurality of cells based on the failover workflow and updates, in the data store, the one or more dependencies for the application based on the failover workflow.

Abstract: The limit switch uses a rolling sprocket mounted on an offset pivot point mounted in a housing in combination with inserts into individual links of the chain. The sprocket engages the chain using spring tension on the pivot point and rolls along the chain as the chain moves with the teeth of the sprocket inserting into the chain link spaces. An insert is attached in a chain link and positioned such that when the curtain reaches the desired terminal position, the inserts are at the point where the sprocket contact the insert. The insert blocks the cog of the sprocket which pushes the sprocket away from the chain and inwardly into the interior of the housing. Inside the housing the limit switch that is activated—either by contact or other means. The activation of the kill switch stops the motor and thus the movement of the curtains.

Abstract: The limit switch uses a rolling sprocket mounted on an offset pivot point mounted in a housing in combination with inserts into individual links of the chain. The sprocket engages the chain using spring tension on the pivot point and rolls along the chain as the chain moves with the teeth of the sprocket inserting into the chain link spaces. An insert is attached in a chain link and positioned such that when the curtain reaches the desired terminal position, the inserts are at the point where the sprocket contact the insert. The insert blocks the cog of the sprocket which pushes the sprocket away from the chain and inwardly into the interior of the housing. Inside the housing the limit switch that is activated—either by contact or other means. The activation of the kill switch stops the motor and thus the movement of the curtains.