7210 SAS platforms use an index file to store the map that indicates the QoS resource allocation to access ports. After a reboot, the file is used to ensure appropriate resource allocation for all access ports that were using the access ingress policy before the reboot. In the absence of an index file, access ports that were configured successfully before the reboot may fail after the reboot. After the configuration file is saved, the index file is stored in flash memory. On system reboot, if the file is found, the system allocates resources as indicated in the stored map. If the file is not found, the system implements a best-fit algorithm and attempts to allocate resources for all access ports on a first-come-first-served basis. If the file is not found after reboot, the saved configuration may not execute successfully because resources may not be allocated to all access ports.
The index file used for the QoS map is different from the file used for storing interface indexes.