用户的两台nexus5548已经使用很多年了，系统版本是5.2.1，一些高级功能在5.2.1中不被支持。因业务需要，需要对这两台5548进行升级，查看文档，得知要将当前版本升级到7.3.5不能一步到位。
为了保证升级的稳定，我制定的升级步骤是先升到6.0.2.N2.7，然后再升级到7.1.4.N1.1，最后再升级到7.3.5。
准备工作：
1、准备相应版本的NX-OS
2、在本机搭建一台FTP服务器。
下面升级马上开始：
升级前做好配置文件的备份，事实证明，这样做是对的！
1、通过命令将系统文件上传到N5548中，命令如下：
5548_A# copy ftp://10.96.1.240/n5000-uk9-kickstart.6.0.2.N2.7.bin bootflash:
5548_A# copy ftp://10.96.1.240/n5000-uk9.6.0.2.N2.7.bin bootflash:
在这里我没有一次性将所有的文件都上传上去，因为空间不够，所以升一个版本上传一个版本。
2、安装升级
用户的环境中是两台5548做的HSRP，在这里我先升级的Active5548_A# install all kickstart bootflash:n5000-uk9-kickstart.6.0.2.N2.7.bin system bootflash:n5000-uk9.6.0.2.N2.7.binVerifying image bootflash:/n5000-uk9-kickstart.6.0.2.N2.7.bin for boot variable "kickstart".[####################] 100% -- SUCCESSVerifying image bootflash:/n5000-uk9.6.0.2.N2.7.bin for boot variable "system".[####################] 100% -- SUCCESSVerifying image type.[####################] 100% -- SUCCESSExtracting "system" version from image bootflash:/n5000-uk9.6.0.2.N2.7.bin.[####################] 100% -- SUCCESSExtracting "kickstart" version from image bootflash:/n5000-uk9-kickstart.6.0.2.N2.7.bin.[####################] 100% -- SUCCESSExtracting "bios" version from image bootflash:/n5000-uk9.6.0.2.N2.7.bin.[####################] 100% -- SUCCESSPerforming module support checks.[####################] 100% -- SUCCESSNotifying services about system upgrade.[####################] 100% -- SUCCESSCompatibility check is done:Module bootable Impact Install-type Reason------ -------- -------------- ------------ ------ 1 yes disruptive reset Non-disruptive install not supported if L3 was enabledImages will be upgraded according to following table:Module Image Running-Version New-Version Upg-Required------ ---------- ---------------------- ---------------------- ------------ 1 system 5.2(1)N1(4) 6.0(2)N2(7) yes 1 kickstart 5.2(1)N1(4) 6.0(2)N2(7) yes 1 bios v3.6.0(05/09/2012) v3.6.0(05/09/2012) no 1 SFP-uC v1.0.0.0 v1.0.0.0 no 1 power-seq v1.0 v3.0 yes 3 power-seq v5.0 v5.0 no 1 uC v1.2.0.1 v1.2.0.1 noSwitch will be reloaded for disruptive upgrade.Do you want to continue with the installation (y/n)? [n] yInstall is in progress, please wait.Performing runtime checks.[####################] 100% -- SUCCESSSetting boot variables.[####################] 100% -- SUCCESSPerforming configuration copy.[####################] 100% -- SUCCESSModule 1: Refreshing compact flash and upgrading bios/loader/bootrom/power-seq.Warning: please do not remove or power off the module at this time.Note: Power-seq upgrade needs a power-cycle to take into effect.Use command 'reload power-cycle' Note: Micro-controller upgrade needs a power-cycle to take into effect.On success of micro-controller upgrade, SWITCH OFF THE POWER to the system and then, power it up.[####################] 100% -- SUCCESSFinishing the upgrade, switch will reboot in 10 seconds.
待系统重启后升级完成。按照同样的方法对standby进行升级。6.0.2.N2升级完成之后，系统没有问题，各应用也正常。
下面接着升级。
在这里我只截取部分内容：
Images will be upgraded according to following table:Module Image Running-Version New-Version Upg-Required------ ---------------- ---------------------- ---------------------- ------------ 1 system 6.0(2)N2(7) 7.1(4)N1(1) yes 1 kickstart 6.0(2)N2(7) 7.1(4)N1(1) yes 1 bios v3.6.0(05/09/2012) v3.6.0(05/09/2012) no 1 power-seq v3.0 v3.0 no 1 SFP-uC v1.0.0.0 v1.0.0.0 no 3 power-seq v5.0 v5.0 no 1 microcontroller v1.2.0.1 v1.2.0.1 no
不知道为什么，在我升级到7.1.4的时候出了点状况，配置文件中关于FC的部分配置丢失了！！还好事前备份了配置文件，迅速修改配置后，系统恢复。
Images will be upgraded according to following table:Module Image Running-Version New-Version Upg-Required------ ---------------- ---------------------- ---------------------- ------------ 1 system 7.1(4)N1(1) 7.3(5)N1(1) yes 1 kickstart 7.1(4)N1(1) 7.3(5)N1(1) yes 1 bios v3.6.0(05/09/2012) v3.6.0(05/09/2012) no 1 power-seq v3.0 v3.0 no 1 SFP-uC v1.0.0.0 v1.0.0.0 no 3 power-seq v5.0 v5.0 no 1 microcontroller v1.2.0.1 v1.2.0.1 no最后从7.1升级到7.3，升级完成后配置文件没有丢失，系统正常！整个升级过程虽然出了点小插曲，不过还算正常。