The telemctl journal command gives you access to features and options of the telemetry journal to assist with system analytics and debug. The telemctl journal has a number of options to help filter records. Use -h or –help to view usage options.

sudo telemctl journal -h
-r,  --record_id        Print record with specific record_id
-e,  --event_id         Print records with specific event_id
-c,  --classification   Print records with specific classification
-b,  --boot_id          Print records with specific boot_id
-i,  --include_record   Include record content
-V,  --verbose          Verbose output
-h,  --help             Display this help message

Journal Output

To see the listing of records in the journal, run the command:

sudo telemctl journal -V

This will produce output like the following:

Table 1. Journal Output
Classification Time stamp Record ID Event ID Boot ID
org.clearlinux/heartbeat/ping Fri 2018-09-21 00:00:57 UTC 269e8e4026e6aa440c4d2ed71e38efcd b3a51b5e62a008ed0b56d1740be67d48 853a75aa-da3b-4356-a085-079abab3ffe1
org.clearlinux/hello/world Fri 2018-09-21 17:53:21 UTC b06c8d31adf5ccc7d5d3f8959d8d3e72 57c64c79a9b911d68f4dab10a00267d7 853a75aa-da3b-4356-a085-079abab3ffe1
org.clearlinux/crash/clr Fri 2018-09-21 17:57:59 UTC b62cd4278672ae3331cf121bc7a8e1c6 b6adb5751382c48eebb7ee007fe1790a 853a75aa-da3b-4356-a085-079abab3ffe1

Each line gives information about a distinct record. The -V or –verbose option adds the header to identify the Classification, Time Stamp, Record ID, Event ID and Boot ID for each record. The journal feature can filter records according to the Classification, Record ID, Event ID and Boot ID by using the -c,:command:-r, -e and -b options accordingly.

Payload Information

From the previous output, you may want to get more information about the record with the “org.clearlinux/crash/clr” classification to help debug a crash. You can use the -c and -i options to see the payload of the record, like this:

sudo telemctl journal -c org.clearlinux/crash/clr -i
org.clearlinux/crash/clr       Tue 2018-09-25 18:43:50 UTC 07ae583edbd13829965d67e9ba97d70c 69c600470769c841649266178375d67e d32c13d1-fda0-49c6-8431-e6c5b29cbefa
Process: /usr/bin/bash
PID: 685
Signal: 11

Backtrace (TID 685):
#0 kill() - []
#1 bash_tilde_expand() - [/usr/bin/bash]
#2 maybe_execute_file() - [/usr/bin/bash]
#3 main() - [/usr/bin/bash]
#4 __libc_start_main() - []
#5 _start() - [/usr/bin/bash]

If you have records of multiple crashes, you can use the :command:’-r’ option to specify the record more precisely, rather than going by classification. You can also specify a classification of record and use the :command:’-i’ option to see the payload of each record with that classification.

Next steps

Adding telemetry to your applications: