A question about phosphor-sel-logger

[Bills, Jason M]

On 5/1/2019 7:36 PM, Will Liang (梁永鉉) wrote:
> Hi,
> 
> Our BMC is using package "phosphor-sel-logger" to support IPMI SEL. it saved the event data in the journal and the id is 1-65534.
> It means it can save 65534 records. Actually, we found the file size of single journal file is around 8MB(the default of journal file is 64MB, it will be separated by 8 files).
> We cannot show all SELs(65534 records) in IPMI. it might be a bug here if we don't limit the maximum.
> 
> Is it necessary to limit the number of SELs to smaller?

Hi Will,

The reason that value is left at 65534 is because in the journal we 
don't have a way to determine how many total SEL entries are possible or 
how much space is left.

With the journal set at 64MB we could see more than 30000 entries.  When 
I made the journal persistent at 6MB, we could see anywhere between 
1200-2000 entries.

We could choose a smaller number for IPMI to report, but it will be 
arbitrary because the journal size can be changed without notifying IPMI.

However, because of the size (1200 entries in 6MB) and other limitations 
with a persistent journal, I'm experimenting with using rsyslog to log 
SEL entries into a syslog file.  This will allow the journal to remain 
volatile while persisting only the logs that we need to.  It will also 
have a more consistent size, so it will be possible to fix the size to a 
smaller number more accurately as you suggest.

You can see my current rsyslog changes here: 
https://gerrit.openbmc-project.xyz/q/topic:"rsyslog+SEL"+(status:open%20OR%20status:merged)

If you are interested, I will also share my rsyslog configuration, but I 
was planning to test it out internally for a while to make sure it will 
work so I don't cause thrash if it has to change again.

Thanks,
-Jason

> 
> BRs,
> Will
>