Why are my logs so short?!

Hi everyone - hope you are keeping well wherever you are in the world.

Wondering if someone might be able to shed a little light on something to help me please:

Over the last couple of nights, my HA GUI has gone down. The night before last I was able to SSH onto the VM running HA. But this morning, I noticed that the VM’s Ethernet interface seemed to have lost its IP address. Running dhclient -r then dhclient via the VM’s console resolved the issue and the web GUI came back up.

I’m trying to understand what happened to cause the interface to “fail”. home-assistant.log doesn’t provide many clues, and my next step is to look at the host VM’s logs. So I’ve copied my public key to USB drive and “Import from USB” to enable root access via SSH on port 22222. I was hoping that I’d be able to use “journalctl” to pull up lots of detail back to the time when I think the network connection went down but the logs only go back about 90 minutes!

Am I missing something? Surely I should be able to see older events in the log than 90 minutes in the past?

And another really weird thing I noticed: in the home-assistant.log file, there are a few lines at the top that have a date in the future (as below). I am completely confused by that!

I’d be grateful for any pointers here.

2020-03-23 03:35:38 WARNING (MainThread) [homeassistant.loader] You are using a custom integration for lutron_caseta_pro which has not been tested by Home Assistant. This component might cause stability problems, be sure to disable it if you experience issues with Home Assistant.

2020-03-23 03:35:38 WARNING (MainThread) [homeassistant.loader] You are using a custom integration for hacs which has not been tested by Home Assistant. This component might cause stability problems, be sure to disable it if you experience issues with Home Assistant.

2020-03-23 03:35:38 WARNING (Recorder) [homeassistant.components.recorder] Ended unfinished session (id=39 from 2020-03-19 20:00:49.275150)

2020-03-20 08:14:34 WARNING (MainThread) [homeassistant.components.template.sensor] Could not render template boiler_boottime, the state is unknown.

Has anyone got any time to give me a little help with this please?

I haven’t asked a really stupid question, have I?