Advanced usage

TODO

layout, lyt-params, alias force unlock

Storage layouts

For now, phobos only supports the 'raid1' storage layout, for mirroring.

The 'simple' storage layout can be obtained by modifiying the number of replicas to 1.

The default layout to use when data is written can be specified in the phobos configuration file, in case multiple are defined:

[store]
default_layout = raid1

If an alias is defined, you can set it as default instead of the layout:

[store]
default_alias = simple

[alias "simple"]
layout = raid1
lyt-params = repl_count=1

Alternatively, you can override this default value by using the 'right' option in your put commands:

# put data using a raid1 layout
phobos put --layout raid1 file.in obj123

phobos dir add --unlock dummy
phobos tape add --unlock dummy
phobos drive add --unlock dummy
# put data using a simple alias
phobos put --alias simple file.in obj123

Layouts can have additional parameters. For now, the only additional parameter is the number of replicas for raid1. This is for now specified using the following env variable:

# put data using a raid1 layout with 3 replicas
PHOBOS_LAYOUT_RAID1_repl_count=3 phobos put --layout raid1 file.in obj123

Extents

When putting an object in Phobos, it will be written on media in potentially The API function associated with this command is phobos_admin_layout_list().