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<p class="MsoNormal">Nancy, <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Just trying to understand, are there any specific scenarios that need aggregation at Head Node using BMC-BMC communication? Have you thought about aggregation at cloud service?
<o:p></o:p></p>
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<p class="MsoNormal">Neeraj<o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> openbmc <openbmc-bounces+neladk=microsoft.com@lists.ozlabs.org>
<b>On Behalf Of </b>Nancy Yuen<br>
<b>Sent:</b> Wednesday, April 29, 2020 3:52 PM<br>
<b>To:</b> OpenBMC Maillist <openbmc@lists.ozlabs.org><br>
<b>Subject:</b> [EXTERNAL] Multiple BMCs in a system: IPMB? Redfish? MCTP?<o:p></o:p></p>
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<p class="MsoNormal">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.<o:p></o:p></p>
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<p class="MsoNormal">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:<o:p></o:p></p>
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i2c/IPMB<o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
usbnet/Redfish<o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
i2c/MCTP/PLDM or something else?<o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
internal network via switch chip/Redfish or MCTP<o:p></o:p></li></ol>
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<p class="MsoNormal"> I'd like to reduce our use of IPMI so I want to avoid (1).<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">----------<br>
Nancy<o:p></o:p></p>
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