Downgrade IOS-XE SD-WAN to IOS-XE

 Downgrade IOS-XE SD-WAN to IOS-XE

As we see now a days the demand of the Software defined WAN and Cisco is using the IOS-XE routers as SDWAN routers by converting IOS-XE images to IOS-XE SDWAN images. But there are always the case where customer may be fall back to the IOS-XE images for the traditional routing on the WAN infrastructure from the IOS-XE SDWAN design.

Here is the way where we are talking about the downgrade procedure of the IOS-XE SDWAN image to IOS-XE cisco image. Here in our example we are using ISR 4400 series router, you can also use any other ISR/ASR router and the procedure is the same.

Fig 1.1- Cisco ISR 4451-X model

As you know if the router has the image of IOS-XE SDWAN and is managed through vManage, the ways to do the changes on the CLI is as below:

  • Change the management of the router from vManage to CLI from the vManage itself.
  • Using the command "config-transaction" to do the changes on the router.

Step1: So the first step is to copy the required IOS-XE image to the bootflash via USB drive.

Step2: You need to connect your router via console in order to login and stop any PNP operation on the router as shown below

NDNA_SDWAN1# pnpa service discovery stop

Step3: Now its time to change the config-register to 0x0

NDNA_SDWAN1# config-transaction
NDNA_SDWAN1#(config)# config-register 0x0
NDNA_SDWAN1#(config)# commit
NDNA_SDWAN1#(config)# end

Step4: Check the config-register is set to 0x0 when the router reboots

NDNA_SDWAN1# show bootvar
NDNA_SDWAN1# reload

Step5: Check the bootflash of the router

rommon 1> dir bootflash
rommon 2> boot bootflash:isr4400-universalk9_ias.17.03.02.SPA.bin

Once you run with the above command, the router reboots with the previous software image.

Step6: Its time to set config-register to the original value 0x2102

router# config terminal
router(config)# config-register 0x2102
router(config)# end
router# wr

You are successfully downgrade the device image from IOS-XE SDWAN to IOS-XE image.