Multiple BMCs in a system: IPMB? Redfish? MCTP?

[Nancy Yuen]

Vijay, I wonder if IPMB would still be used in later generations or would
something like MCTP be considered?
----------
Nancy


On Wed, Apr 29, 2020 at 5:42 PM Vijay Khemka <vijaykhemka at fb.com> wrote:

> Nancy,
>
> We have multiple hosts which has a small controller called BIC (Bridge
> IC). This BIC on each host connected via i2c to main BMC and communicates
> through ipmi messages to BMC over IPMB/i2c.
>
>
>
> Regards
>
> -Vijay
>
>
>
> *From: *Nancy Yuen <yuenn at google.com>
> *Date: *Wednesday, April 29, 2020 at 5:25 PM
> *To: *Vijay Khemka <vijaykhemka at fb.com>
> *Cc: *OpenBMC Maillist <openbmc at lists.ozlabs.org>
> *Subject: *Re: Multiple BMCs in a system: IPMB? Redfish? MCTP?
>
>
>
> Neeraj, I was not considering aggregation in this case, just having the
> intermediate BMC "route".
>
>
>
> Vijay, thanks.  I was wondering what your applications for IPMB were for.
> What's the rationale for using IPMB vs something else?  In your multihost
> system, one BMC supports multiple host CPUs?  Are there also multiple BMCs?
>
>
> ----------
> Nancy
>
>
>
>
>
> On Wed, Apr 29, 2020 at 5:15 PM Vijay Khemka <vijaykhemka at fb.com> wrote:
>
> Hi Nancy,
>
> We are currently using (1) in our current multi host design. Option (3)
> also looks good.
>
>
>
> Regards
>
> -Vijay
>
>
>
> *From: *openbmc <openbmc-bounces+vijaykhemka=fb.com at lists.ozlabs.org> on
> behalf of Nancy Yuen <yuenn at google.com>
> *Date: *Wednesday, April 29, 2020 at 3:53 PM
> *To: *OpenBMC Maillist <openbmc at lists.ozlabs.org>
> *Subject: *Multiple BMCs in a system: IPMB? Redfish? MCTP?
>
>
>
> I've talked with some people a while back (long while back) about multiple
> BMCs in a system.  Either for redundancy or managing separate parts of a
> system.   I'm wondering what other people are thinking in this area if at
> all.
>
>
>
> We are considering similar designs and I'm looking into options for
> BMC-BMC communications.  Some BMCs may not be externally accessible. Here
> are some options that we've looked at:
>
>    1. i2c/IPMB
>    2. usbnet/Redfish
>    3. i2c/MCTP/PLDM or something else?
>    4. internal network via switch chip/Redfish or MCTP
>
>  I'd like to reduce our use of IPMI so I want to avoid (1).
>
>
>
> ----------
> Nancy
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ozlabs.org/pipermail/openbmc/attachments/20200429/a131494d/attachment.htm>