From what I have learned, Centos 7 (by default) keeps log journal entries in memory only so these are lost when machine is rebooted. I'm comfortable with the fact that I can only see messages from current boot.
Putting syslog forwarding aside, how can I list all of the entries already stored in journal for the current boot? I tried:
[root@box ~]# journalctl -b 0 -- Logs begin at Wed 2015-12-02 16:32:14 CET, end at Wed 2015-12-02 18:09:55 CET. --
but it doesn't show old entries, only the entries for (as you can see) the past few hours.
My machine has actually been running for several days, though:
[root@box ~]# uptime 18:12:38 up 19 days, 4:28, 1 user, load average: 0.34, 0.39, 0.57
I'd like to see the logs for that whole period.