[OpenBmc][JournalD] Persisting Journal Logs

[Alisa Gataullina]

On Thu, 2022-12-01 at 14:04 +0000, Rohit Pai wrote:
> I am running open bmc with Linux 5.15 and systemd 251 (251.2+).
> I have configured persistent logging for journal.
> /etc/systemd/journald.conf
> [Journal]
> Storage=persistent
>  
> Created folder /var/log/journal. This is mounted on mtd flash
> partition.
> The rootfs has overlay with RO filesystem and RW filesystem coming
> from mtd partition.
>  
> ls -alt /var/log/journal/
> drwxr-sr-x    2 root     systemd-         0 Jan  1 00:03
> 2b4305f670484d1fa6b9c4deee336b91
>  
> Jouranld creates a folder under /var/log/journal but I dont see
> anything getting stored here ever. 
> I don't see journal being persistent across reboots.
> Journal logs are kept only in /run/log/journal, and this is tmpfs in
> the system and gets erased on each reboot.
> I have tried journalctl --flush to see if anything gets pushed to
> inside /var/log/journal but nothing is stored apart from the folder
> name. 
> journalctl --rotate also has no impact.
> I seem to be doing everything as per the journalctl documentation but
> still it’s not working.
>  
> Anyone else has seen this issue, any help?
>  
> Thanks 
> Rohit PAI 

Hello

To change journal log directory:

systemd-tmpfiles --create --prefix /var/log/journal
systemctl restart systemd-journald

It needs to check journal log rotate settings. But this isn't
recommended way for embedded system- too many rewriting cycles. The
best way is to use remote syslog

To mount /var/log on persistent storage with yocto you could add  
VOLATILE_LOG_DIR = "no"  into conf file of machine.
After that all RedFsh, IPMI and all others logs defined with
rsyslog.conf will be there on persistent storage. Also yocto created
directory /var/log/journal but journal use default log path
/run/log/journal. And you need to setup it.

Best Regards,
Alisa