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<p class="MsoNormal">Hi Nancy,<o:p></o:p></p>
<p class="MsoNormal">We are currently using (1) in our current multi host design. Option (3) also looks good.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards<o:p></o:p></p>
<p class="MsoNormal">-Vijay<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">openbmc <openbmc-bounces+vijaykhemka=fb.com@lists.ozlabs.org> on behalf of Nancy Yuen <yuenn@google.com><br>
<b>Date: </b>Wednesday, April 29, 2020 at 3:53 PM<br>
<b>To: </b>OpenBMC Maillist <openbmc@lists.ozlabs.org><br>
<b>Subject: </b>Multiple BMCs in a system: IPMB? Redfish? MCTP?<o:p></o:p></span></p>
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<p class="MsoNormal"><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"><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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