Nexus

关于N7K的Fabric module的几个问题说明：
1.Fabric 1迁移到Fabric 2时，必须在Cisco NX-OS 6.0(x) or a later release；
2.N7009不支持Fabric 1；
3.Fabric 1在线迁移到Fabric 2时，必须在12小时内完成，否则有系统信息提示，原文如下：When upgrading fabric modules, you must replace all of the Series 1 fabric modules in the switch with Series 2 fabric modules within 12 hours or you will see a syslog message that reminds you to complete the upgrade.
4.Fabric 1离线迁移到Fabric 2时，在两个模块共存时启动交换机，思科官方给出了两种截然相反的说法，原文如下：
You can replace a Series 1 fabric module with a Series 2 module in the Cisco Nexus 7010 and 7018 switches during operations, but while there is a mix of fabric module types, all of the fabric modules perform as Series 1 fabric modules. If you power up a switch with two types of fabric modules installed, only the Series 1 fabric modules will power up. To utilize the Series 2 fabric module capabilities, all of the installed fabric modules must be Series 2 fabric modules.
If you power up a switch that has both types of fabric modules installed, only the Series 2 modules power up. If you need the Series 1 modules to power up, you must first power off all of the Series 2 modules before the Series 1 modules can power up.

关于I/O模块与Fabric的关系中，在培训中提到如果采用F2的I/O模块，需要5块Fabric 2的模块，这里需要说明几点：
1.如果采用单块F2的I/O模块，可以只配置2块Fabric 2的交换矩阵达到1+1的冗余，而不需要考虑是否线速，因为同一F2模块的不同端口之间数据传输不需要经过交换矩阵；
2.基于上面这点，I/O模块与Fabric的关系，不是说没有Fabric就不能使用I/O模块或I/O模块启不来，而是不同I/O间的数据传输需要多大的带宽。
3.M1千兆I/O模块因为连接背板带宽是40Gbps，双向80Gbps，所以必须有一块Fabric 1模块正常工作，否则不能工作。