Add _MACHINE_ID field to unique record identifier

[spbnick]

Since journald can also receive logs from other hosts, it is possible that TLOG_REC values can collide in the same journal, since they would be generated on separate hosts.

Use _HOSTNAME in addition to TLOG_REC to uniquely identify recordings. However, if it's not actually guaranteed to be unique (likely), check if there is a more reliable way to identify origin hosts for journal messages.

See https://www.freedesktop.org/software/systemd/man/systemd-journal-remote.html and https://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html

[sabbaka]

What about _MACHINE_ID= ( The machine ID of the originating host, as available in machine-id(5) )? https://www.freedesktop.org/software/systemd/man/machine-id.html

[spbnick]

Sounds good. Could you please verify that it is preserved on journal forwarding and you can actually distinguish messages coming from different hosts? The best test would be to do it with tlog messages and verify that recordings can be distinguished.

On Aug 21, 2017 10:14 AM, "Kyrylo Gliebov" notifications@github.com wrote:

What about _MACHINE_ID= ( The machine ID of the originating host, as available in machine-id(5) )?

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[sabbaka]

journalctl _MACHINE_ID=<my_machine_id> and it worked. I'll check for journal forwarding also, but I will need somehow to have different logs from different machines, right?

[spbnick]

Hmm, I guess when you forward journal log from one machine to another the other machine log just ends up in the target machine's journal.

[sabbaka]

I've add machine ID, but strictly from the front-end perspective, we should also have the same session ID stored in journal. Right?