Aggregating data

To aggregate the data, use the -C option.

No matter what option is being used to select devices, the result will have data of LUN granularity. The -C option takes one of the following parameters:

a
Aggregate all data on a FCP channel level. That is, data for all LUNs that are connected through the same FCP channel will be aggregated.
u
Aggregate all data on a FCP device level. That is, data for all LUNs that are connected through the same FCP device will be aggregated.
p
Aggregate all data on a port level. That is, data for all LUNs that are connected through the same port will be aggregated.
m
Aggregate all data on a multipath device level. Only useful when devices were specified through -d. That is, data for all paths available for a multipath device will be aggregated.
A
Aggregate all data on a global level. That is, data for all specified LUNs will be aggregated.

If you select devices using -c, -u, -p, -l, -m or -d, only those devices will be considered for aggregation. For example, consider multipath device 36005076303ffc1040002120 with paths sda and sdb, and 36005076303ffc1040002121 with paths sdc and sdd.

Example: If you run:
-C m -m 36005076303ffc1040002120 -d sdc
all paths (namely sda and sdb) for device 36005076303ffc1040002120 will be aggregated, but only a single one for multipath device 36005076303ffc1040002121.