HP Cisco Nexus 5000 Cisco Nexus 5000 Series Switch CLI Software Configuration - Page 350

CFS Support for Applications Using Cisco Fabric Services CFS supports a protocol that reduces the number of merges required to one by handling the complexity of the merge at the CFS layer. This protocol runs per application per scope. The protocol involves selecting one switch in a fabric as the merge manager for that fabric. The other switches do not have a role in the merge process. During a merge, the merge manager in the two fabrics exchange their configuration databases with each other. The application on one of them merges the information, decides if the merge is successful, and informs all switches in the combined fabric of the status of the merge. In case of a successful merge, the merged database is distributed to all switches in the combined fabric and the entire new fabric remains in a consistent state. You can recover from a merge failure by starting a distribution from any of the switches in the new fabric. This distribution restores all peers in the fabric to the same configuration database. CFS Support for Applications CFS Application Requirements All switches in the network must be CFS capable. Switches that are not CFS capable do not receive distributions and result in part of the network not receiving the intended distribution. CFS has the following requirements: • Implicit CFS usage-The first time you issue a CFS task for a CFS-enabled application, the configuration modification process begins and the application locks the network. • Pending database-The pending database is a temporary buffer to hold uncommitted information. The uncommitted changes are not applied immediately to ensure that the database is synchronized with the database in the other switches in the network. When you commit the changes, the pending database overwrites the configuration database (also known as the active database or the effective database). • CFS distribution enabled or disabled on a per-application basis-The default (enable or disable) for CFS distribution state differs between applications. If CFS distribution is disabled for an application, then that application does not distribute any configuration nor does it accept a distribution from other switches in the network. • Explicit CFS commit-Most applications require an explicit commit operation to copy the changes in the temporary buffer to the application database, to distribute the new database to the network, and to release the network lock. The changes in the temporary buffer are not applied if you do not perform the commit operation. Enabling CFS for an Application All CFS-based applications provide an option to enable or disable the distribution capabilities. Applications have the distribution enabled by default. The application configuration is not distributed by CFS unless distribution is explicitly enabled for that application. Verifying Application Registration Status The show cfs application command displays the applications that are currently registered with CFS. The first column displays the application name. The second column indicates whether the application is enabled or disabled for distribution (enabled or disabled). The last column indicates the scope of distribution for the application (logical, physical, or both). Cisco Nexus 5000 Series Switch CLI Software Configuration Guide 304 OL-16597-01