Mike, The 6500 and 4500 have the "switch fabric" on the supervisor engines, so by having dual supervisors, you in effect have a redundant fabric.
The 6748 actually has 4 traces, each 20G. 2 traces connect to the active supervisor containing the active switch fabric. The remaining 2 traces are standby connections to the standby supervisor/fabric. So, when a supervisor engine and its fabric fails, the 2 standby traces are enabled and the full 40G of bandwidth remains. You never, under normal circumstances, have only a single trace active on 6748. Newer versions of IOS provide a "hot standby" fabric feature which allows this fabric trace switch over to happen faster - roughly 50ms. For the best in redundant designs, consider the Nexus 7000, where the switch fabric is decoupled from the supervisor engines into a series redundant "fabric modules" installed into the back of the switch. Should a supervisor engine fail in Nexus 7000 there is ZERO impact to the switch fabric, because the supervisor engine does not forward data plane traffic. Cheers, Brad Hedlund [email protected] http://www.internetworkexpert.org On 3/31/09 9:05 AM, "Mike Louis" <[email protected]> wrote: > I have a solution design that requires redundant switch fabrics. I am > interpreting this beyond just have redundant supervisors meaning redundant > backplanes on the switch cards. Do the 6500 and 4500 support redundant > fabrics? Will a 6748 function with one trace failed? > ________________________________ > Note: This message and any attachments is intended solely for the use of the > individual or entity to which it is addressed and may contain information that > is non-public, proprietary, legally privileged, confidential, and/or exempt > from disclosure. If you are not the intended recipient, you are hereby > notified that any use, dissemination, distribution, or copying of this > communication is strictly prohibited. If you have received this communication > in error, please notify the original sender immediately by telephone or return > email and destroy or delete this message along with any attachments > immediately. > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
