User's Guide

Remarks
The command will display a table with the mapping of the historians to the
sensor IDs, as well as their status (active/deleted). The stream to which a historian
belongs will be also shown. A "deleted" historian is one that is no more active, it
will be "recycled" when new sensor will be added after all historians have been
used (currently 128).
Note that deleted historians do not belong to any stream.
To look-up the historian for a certain tag, first use the attr -t command to identify
the ID of a tag (or from the M2M Gateway: select the sensor, click the Info tab
there you will find the Public Node ID); using the ID, look-up the historian in the
table shown by the hist map command.
Example
: hist map
Hist. Tag ID Stream Status
------------------------------
0 77180 0 active
1 77179 0 active
2 78482 1 active
3 78481 1 active
4 78480 1 active
5 78479 1 active
6 78478 1 active
7 78477 1 active
[…]
11 79625 - deleted
12 79624 - deleted
13 79623 - deleted
[…]
17 79631 4 active
18 79632 4 active
19 79633 4 active
20 79955 4 active
4.2.14. hist purge
Description
Used to purge (delete) the historians.
Usage
hist purge [-y].
Remarks
Purge all historians. If the -y option is used, then the historians will be purge
without asking for a confirmation, otherwise the user will be prompted for a
confirmation. The command takes about 20 seconds to complete.
WARNING: all sensor data stored in the local data base will be lost!
Example
: hist purge
All stored data will be lost. Proceed? (y/n) y
Please wait, it will take some time...
Historian data purged
4.3. Data Acquisition Legacy Commands
The commands in this group are maintained to assure compatibility with legacy systems. Their use is not
recommended for new implementations; use a variant of the dacq command instead. The main difference
between the equivalent dacq commands and the legacy commands is that for the former a valid
configuration is required to access the sensors, whereas for the later it is not.
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