Meru Technical Note - What are the steps to successfully 'downgrade' a Meru System Director 5.x controller to SD 4.x software code running nplus1?

[nsamuel]

Description

What are the steps to successfully "downgrade" a Meru System Director  5.x controller to SD 4.x software code running nplus1?

Scope

KB ARTICLE TYPE: Configuration

RELATED PRODUCTS: All Controllers

RELATED SOFTWARE VERSIONS: All

KEYWORDS: downgrade

Solution

Controller SD Downgrading Procedure. Use when shipping a new or RMA’d controller to a customer that requires an older version of System Director than was flashed on to the (new) replacement controller.

DESCRIPTION: Commands to downgrade the controllers to an older firmware code, including when running the Nplus1 redundancy setup.

CONFIGURATION STEPS:

iosCLI Steps:

(If not running the nplus1 feature please proceed to “STEP 3”)

STEP 1: Stop Nplus1 on the Slave controller

“configure terminal”
“nplus1 stop”

STEP 2: Stop Nplus1 on the Master controllers

“configure terminal”
“nplus1 stop”

STEP 3: Verify in the release notes of the proposed upgrade version if it is supported to directly upgrade to that version, from the current firmware version on the controller. Also be sure to backup your configuration and use the “calendar set” to set the correct time and date (format mm/dd/yyyy hh:mm:ss)

STEP 4: Start tftp/ftp server on host machine with access to the controller CLI

STEP 5: type “copy tftp://x.x.x.x/filename .” where x.x.x.x is the IP address of the tftp server, filename is the name of the new firmware code file to be transferred. Make sure there is a period (.) at the end of the command, as shown above.

STEP 6: After successful transfer of the new code onto the controller, type “show flash” to verify that the new code is available on the controller.

In a case of a 5.x to 4.x downgrade it is recommended to downgrade to 4.0-150 first before upgrading to a 4.x subsequent release (e.g. 4.0-158). Also it is recommended to record the Serial Number of the unit as the downgrade process deletes the electronic record of it.

STEP 7: type “configure terminal”

STEP 8: type “auto-ap-upgrade disable”

STEP 9: type “exit”

STEP 10: type “upgrade system xxxx” where xxxx is the name of the new firmware code to which the controller has to be upgraded.

STEP 11: The controller will upgrade the APs first, and then upgrade itself, after which the controller will reboot and come online with the new firmware code.

STEP 12: type “configure terminal”

STEP 13: type “auto-ap-upgrade enable”

STEP 14: type “exit”

STEP 15: type “show controller” to view the controller firmware version. After a downgrade it is possible the Serial Number will show as “N/A” (Not Available). Please refer to Step 18 on how to restore the Meru Serial Number.

STEP 16: Start Nplus1 on the Master controllers

“configure terminal”
“nplus1 start”

STEP 17: Start Nplus1 on the Slave controller

“configure terminal”
“nplus1 start”

STEP 18: Restore the Serial Number (requires root access). Enter the commands as shown below in the Command Line Interface of the controller:

default# log root

Password: xxxxxxxx (Please contact Meru CS for 4.x or 5.x password)

default# cd  /opt/meru/etc

default# echo "1609MC151040">meru-serial-number     

default# cat meru-serial-number

1609MC151040 (sample only)

3608MC10001148

default# exit

logout

default# poweroff controller

Are you sure you want to poweroff the controller [y|n]? y

TEST RESULTS: Nplus1 must always be stopped on the slave controller first, and then the master controllers.

LIMITATIONS IF ANY: If there are a large number of APs on the network, it may take several minutes for the controller to upgrade these APs before upgrading itself and rebooting if auto AP upgrade is turned on.

Including Addendum Procedure to change default boot image on controller below (optional). 

Procedure to change the default image from 2.6 (5.x-x) to 2.4 (4.0-x) based boot image
=========================================================

# Create a directory under /tmp

mkdir /tmp/part1

# Mount the first partition on the flash to this directory

mount /dev/hda1 /tmp/part1

# Edit the grub.conf file under grub folder

vi /tmp/part1/grub/grub.conf

# If the customer had upgraded to 5.x-x the default image would be set to 1
# change this to 0 (Zero) - to set the default boot image to 2.4-x (4.0-x)
# you would see an entry 'default 1' - change this to as below:

default 0

# save the file

# Be sure to umount  (During this step, you should not run umount command
# from being anywhere under the directory /tmp/part1. Running it from anywhere
# else is okay.. (say for example - /root is okay)

umount /tmp/part1

# Remove the temporary directory

rmdir /tmp/part1

# Reboot & ensure that the default boot image is 2.4-x (4.0-x)