evms_query - Query for information about EVMS and its components.

evms_query [global_options] <command> [command_options] [name]

global_options: [-d debug_level, --debug-level debug_level] debug_level = [0-9] | [critical | serious | error | warning | default | details | entry_exit | debug | extra | everything] [-l log_file_name, --log-file log_file_name] [-n node_name, --node-name node_name] [-v, --verbose] verbose mode [-h | -? | --help] display this help

commands: info details plugins disks segments regions feature_objects objects containers volumes

command_options: [-i, --info] [-a, --above] [-b, --below]

The evms_query utility is used for gathering a variety of information about EVMS and its components. This utility has several different "commands," each of which provides a particular type of information. Each command can take a "name" as an optional argument. This name can be the name of any component in EVMS--any plug-in, volume, container or storage-object (disks, segments, regions, and feature-objects).

The following options can be used with evms_query:

-d, --debug-level debug_level

Specify the amount of information that should be written to the log file. A numerical value between 0 and 9 can be specified, where a larger number generates more logging information. The following text values are also allowed:

critical
serious
error
warning
default
details
entry_exit
debug
extra
everything

"Critical" generates the least information and "everything" generates the most information. The default debug level is "default" or "5."

-l, --log-file log_file_name

Specify the location of the log file. The default value is /var/log/evms-engine.log.

-n, --node-name node_name

Specify the node in the cluster on which the query should be performed. The default value is the local node. If EVMS is not running in a cluster, this option is ignored.

-q

Do not display any status information.

-v

Display verbose status information about the progress of the query.

-h, -?, --help

Display a summary of the options available for evms_query.

info [name]

Display basic information about an EVMS component. If a name is given, display information about that item. If no name is given, display general information about EVMS.

details [name] [extra_tag]

Display more detailed information about an EVMS component than is available from the info command. Like the info command, if a name is given, display detailed information about that item. If no name is given, display general information about EVMS.

The details for some items may indicate that "extra information" is available. In this case, the "name" of that particular information entry can be used as an "extra_tag." If the details command is run again with the same name and this "extra_tag," detailed information related to that tag will be displayed (instead of the normal detailed information).

plugins [name]

Display a list of plug-ins. If no name is given, display a list of all plug-ins that are currently loaded. If a name is given, display the plug-in that produces that item.

disks [options] [name]

segments [options] [name]

regions [options] [name]

feature_objects [options] [name]

objects [objects] [name]

containers [objects] [name]

volumes [objects] [name]

Display a list of the specified type. If no name is given, display a list of all items that match that type. If a name is given, display a list of all items that match the type and are either descendants or ancestors of the specified item.

When determining descendant/ancestor relationships, the disks are considered to be the bottom of the volume/object stack, and the volumes are considered to be the top of the volume/object stack. A descendant is some item lower in the stack (a child), and an ancestor is some item higher in the stack (a parent).

Each of these commands can take additional options before the name is specified.

-i, --info

Normally, a list of simple names is displayed for these lists (one name per line). If the "--info" option is given, each list entry has its basic information displayed as well. This is the same information that would be displayed if the info command were run for that name. The plugins command also supports this option.

-a, --above, -b, --below

Force the command to search upward or downward in the volume/object stack for items matching the desired type. In most cases, evms_query can figure out the correct direction to search based simply on the name of the "source" item and the desired list type. However, in some situations, the direction can be ambiguous. This normally happens when the desired list type is the same type as the specified "source" item. It can also happen when displaying a list of containers, because containers can exist at different levels in the stack.

evms_query info hdb

(Display basic information about the disk hdb.)

Output:

Name: hdb Type: Disk Data Type: Data Device Number: 3,64 Size (sectors): 58633344 Plugin: LocalDskMgr

evms_query details lvm/system

(Display detailed information about the container
     lvm/system.)

Excerpt From Output:

Name: Available_PEs Title: Available PEs Description: Number of extents available for allocating to regions

Value: 95

Name: Current_PVs (extra info available) Title: Number of Objects (PVs) Description: Number of objects consumed by this container Value: 2

Name: Current_LVs (extra info available) Title: Number of Regions (LVs) Description: Number of regions produced by this container Value: 2

Name: Max_LV_Size Title: Maximum Region Size Description: Maximum possible size of any region in this container for the given PE size Value: 536870912 sectors

evms_query details lvm/system Current_PVs

(Display detailed information about the container lvm/system,
     specifically regarding "Current_PVs".)

Output:

Name: PV1 (extra info available) Title: Object (PV) 1 Value: hdb1

Name: PV2 (extra info available) Title: Object (PV) 2 Value: hdb2

evms_query regions

(Display a list of all regions.)

Output:

lvm/system/region1 lvm/system/region2 lvm/system/Freespace

evms_query segments --info lvm/system/region1

(Display a list of all segments (along with basic info)
     that are "children/descendants" of the region
     lvm/system/region1.)

Output:

Name: hdb2 Type: Segment Data Type: Data Device Number: 253,1 Size (sectors): 1023120 Plugin: DosSegMgr

Name: hdb1 Type: Segment Data Type: Data Device Number: 253,0 Size (sectors): 1023057 Plugin: DosSegMgr

evms(8), evms_activate(8), evms_gather_info(8), http://evms.sourceforge.net/

Kevin Corry.