Snapshot views
A snapshot view uses a host's native file system to hold versions of file and directory elements that have been loaded from a VOB. After the snapshot view has been created, versions of file and directory elements must be loaded (copied) into the snapshot view directory.
The snapshot view directory is usually on the local host, but can be located on any host that the view server and the client can access over the network, even if that host does not have DevOps Code ClearCase® installed. In addition to copies of versions, the snapshot view directory can contain view-private objects. It also contains some files created to help manage the view.
- View database. The db subdirectory contains the binary files managed by the embedded database management system. The database keeps track of the loaded VOB objects and checked-out versions in the view.
- Administrative directory. The admin directory contains data on disk space used by the view. Periodically, the DevOps Code ClearCase scheduler runs a job that generates this data.
Snapshot views cannot contain derived objects. You can run clearmake and omake in a snapshot view, but their build auditing and build avoidance features are disabled.
A snapshot view must have an associated view_server process, which can run on the local host or another host.
For administrative purposes, it is important to know whether the view storage directory of a snapshot view is collocated (is a subdirectory of the snapshot view directory). For example, when you back up or move a snapshot view, you must include both the snapshot view directory and the view storage directory. For more information, see Moving a view.
View storage directory
The view storage directory contains the following files and subdirectories, which are created and modified by DevOps Code ClearCase commands and must never be modified in any other way:
- .access_info
- A file of view access event information that is periodically updated by the view server.
- .pid
- A one-line text file that stores the process ID of the view's view_server process.
- admin
- A directory that contains administrative data related to the amount of disk space a view is using. Use cleartool space –view to list this data.
- config_spec
- A file that stores the view's current config spec, in the form displayed by catcs.
- .compiled_spec
- A modified version of config_spec, which includes accounting information.
- .identity
- On Linux or the UNIX system, a subdirectory whose zero-length files establish the view's owner and group memberships.
- identity.sd
- On Windows®, a security descriptor created for views stored in a FAT or FAT32 file system. Views stored in NTFS file systems include security descriptors in the file system ACL and do not need this file.
- .s
- A subdirectory that implements the view private storage area.
- db
- A subdirectory containing the files that implement the view's embedded database.
- .view
- A file that holds the view's universal unique identifier (UUID) and other attributes
- view_db.state
- A file that records the current state of the view.
View database
The view database subdirectory, db, contains these files, all of which are created and modified DevOps Code ClearCase commands and must never be modified in any other way:
- view_db.dbd
- A compiled database schema, used by embedded database routines for database access. The schema describes the structure of the view database.
- view_db_schema_version
- A schema version file, used by embedded database routines to verify that the compiled schema file is at the expected revision level.
- view_db.d0n view_db.k01
- Files in which the database's contents are stored.
- vista.*
- Database control files and transaction logs.
For a snapshot view, the view database keeps track of the loaded VOB objects and checked-out versions in the view.