Backing up log files to SD card
The following SNMP‑based monitoring units are equipped with an internal micro SD card reader (as of 03/2019):
- Didactum Monitoring System 300
- Didactum Monitoring System 500 & 500 DC (48V)
The above monitoring units can optionally be equipped with a micro SD card to record log data, log files, sensor data, video images, and configuration data. Currently, micro SD cards with capacities of 4/8/16/32/64 GB are supported. Please use only HC micro SD cards from a reputable brand manufacturer. The SNMP‑based monitoring units from Didactum support micro SD cards formatted with “FAT32” or “Ext4”. Before using the micro SD card in the monitoring unit, it must be formatted. To access the SD card settings, go to the “System settings” menu in the web interface of the monitoring unit and select the “SD card” tab.
Note:
If your SNMP‑based monitoring unit is not equipped with a micro SD card reader, this menu entry will not be listed in the Web GUI.
| # | SD card setting | Description |
|---|---|---|
| 1 | Current state | Displays the current status of the micro SD card (normal / ejected / not connected). |
| 2 | Mount point | Mount point / directory structure of the micro SD card. |
| 3 | Full Size | Displays the storage capacity of the micro SD card. |
| 4 | Free Size | Displays the remaining free storage capacity. |
| 5 | Enable logging to SD card | Enables or disables logging to the micro SD card. |
| 6 | Save video files | Enables or disables recording of video images from the connected Didactum video camera. |
| 7 | Enable detailed logging | Enables or disables recording of real‑time sensor data for selected sensors. |
| 8 | Duration of logging in each file | Defines the logging duration per file. When the time is reached, a new log file is automatically created. The duration can be set between 15 minutes and a maximum of 3 hours. |
| 9 | Maximum number of files | Defines the maximum number of files allowed in the micro SD card directory. The oldest files are automatically overwritten. The number of files can range from 10 to 10,000. |
| 10 | Lifetime of files | Desired retention time for files stored on the micro SD card (e.g., 1 week). Older files are automatically deleted. |
| 11 | Contents of the SD card | Provides a link to the contents of the micro SD card. |
Important notes from the technical editorial team:
Before removing the micro SD card, it must be ejected from the monitoring unit. Without prior “unmounting”, the risk of data loss exists. Log files are written to a directory on the micro SD card whose name is formed from the device type name and the hostname. If the user does not specify a name (default hostname), the IP address of the monitoring unit is used to form the directory name. This directory contains the log files, change‑dump files (diff) and full dump files (full).
The log files are named according to date and time of creation, e.g., “2012.10.11_15‑46‑15.log”. The file extension indicates the content: “Log” for log files, “diff.csv” for change‑dump files, and “full.dump” for full dump files. At the beginning of the log file, service information such as Didactum device type, firmware release, and IP address is stored. The log files and full dump files are written in text form. Changes in dump files (diff) and the measured values of the Didactum sensors are recorded in CSV format. The widely used CSV data format is supported by programs such as Microsoft Excel.
Example log file
The log file created by the monitoring unit looks like this (excerpt):
# # Device type: "Didactum 500", Firmware version: "2.7.4 b513". # Hostname: "hostname", IP: "192.168.2.143", MAC: "d9:80:39:9e:93:a5" # Thu Dec 11 16:29:20 2012 message: USB Flash was inserted Thu Dec 11 16:29:25 2012 state: Element Onboard Temperature (id=201001) changed state from "warning" to "normal" Thu Dec 11 16:29:25 2012 state: Element Onboard Voltage DC (id=203001) changed state from "unknown" to "normal" Thu Dec 11 16:29:26 2012 state: Element Dry‑1 (id=101001) changed state from "unknown" to "warning" Thu Dec 11 16:29:26 2012 state: Element Dry‑2 (id=101002) changed state from "unknown" to "normal" Thu Dec 11 16:29:30 2012 message: System started up and ready Thu Dec 11 16:29:41 2012 state: Element GSM Modem (id=404001) changed state from "warning" to "normal" |
The dump file (change dump) is written every 60 seconds and lists the sensor IDs and sensor values that have changed during that interval. Every 60 minutes, the measured values of all sensors are written into the dump file, even if the values have not changed.
The CSV file looks like this (excerpt):
The full backup file is created by the SNMP‑based monitoring unit every 60 minutes. This file contains a complete description of all elements and modules. The file looks like this (excerpt):
Thu Dec 11 16:29:52 2012 [101001]={module:"2022";clas:"discrete";type:"dry";name:"Dry‑1";state:"normal";hwport:"1";value:"0";utype:"";reverse:"0";}; [101002]={module:"2022";clas:"discrete";type:"dry";name:"Dry‑2";state:"normal";hwport:"2";value:"0";utype:"";reverse:"0";}; [203001]={module:"2020";clas:"analog";type:"voltage";name:"Onboard Voltage DC";state:"normal";value:"12.2";vmax:"24.0";vmin:"0.0";low_alarm:"9.0";low_warning:"11.0";high_warning:"13.0";high_alarm:"14.0";at0:"1.000";at75:"0.000";um:"V";}; [403001]={module:"2031";num:"1";clas:"devhwr";type:"usb‑cam";name:"USB Web camera";url:"";fps:"1.0";username:"";password:"";resolution:"320x240";}; [404001]={module:"2030";clas:"devhwr";type:"GSM modem";state:"normal";name:"GSM modem";value:"90";imei:"866104023288015";pin:"";sms_centre:"+79168999100";allowed:"";status:"found, ready";verbosity:"2";}; |
Last change: 29.03.2019