FCS Offline Support

File Collaboration Server (FCS) file resources can be distributed in different global locations worldwide. If a remote server goes offline, the network can still function as long as an alternative server exists.

This topic describes:

This page discusses:

See Also
Moving a Location
FCS Processing
FCS Synchronization

As the adoption of FCS increases, it becomes necessary for essential operations to continue uninterrupted, even if one or more remote FCS servers goes offline. FCS captured stores and locations can have an offline or online status. If a store/location is declared offline, an alternative store/location is used, if available. User operations would then fail only if no alternative store/location exists, thus reducing the system-level impact of any single FCS going offline. Examples of scenarios where this might be the case could include:

  • Scheduled server maintenance—An FCS location must be taken down for maintenance operations.
  • Unexpected server down—An FCS location is determined to be either down or unreachable.
  • Regular server status monitoring—Although there is no product that supports this case out-of-the-box, it is possible to monitor programmatically all FCS locations and declare their status as online or offline, respectively.

FCS Offline Scenarios

The following are some of the available options for handling offline FCS scenarios:

Location Override
In this case, the FCS does not attempt to replace the offline server with an alternative. If a location is offline, an error is raised.
Preferred Location
In this case, the FCS attempts to use another online location if the original preferred location is offline. If all FCS locations are offline, an error is raised. For checkin, the store is used as the next preferred location. If that store is also offline, an arbitrary online location (for that store) is used.

Operations that rely on an FCS location would inherit the behavior and error out. For example, copy bus could fail if an FCS copy is needed and the corresponding location is offline.

Source Location
In the case of sync, assuming that the target location is online (if a preferred location was selected), the FCS attempts to use a source location that is online. If all FCS locations that have the source file are offline, an error is raised.

Impacted MQL Commands

The following MQL commands are impacted if an FCS location is offline:

sync store
Returns an error if one of the specified locations is offline.
sync location
Returns an error if one of the specified location is offline.
tidy store
Tidies only those locations that are online.
purge store
Purges only those locations that are online. It returns an error if the store itself is offline.
purge location
Returns an error if the specified location is offline.
rechecksum store
Performs a rechecksum only on those locations that are online.