How to sanitize a cisco nexus switch.
This is needed when you want to put your equipment back in original configuration and don’t want to let any information on it.
To sanitize the switch the following steps need to be done:
1. Erase all configurations
2. reload without saving
3. Update the firmware
1) Erase all old configurations
To erase both configuration files (and start over), enter the write erase commands:
You cane have the different options with the ? mark.
write erase ?
<CR>
boot Destroys boot configuration on persistent media
debug Destroys debug configuration on persistent media
poap Removes System-wide POAP disable configuration on persistent media
we will use all the options to get rid of all the old informations.
The boot option erases the boot variable definitions and the IPv4 configuration on the mgmt0 interface.
switch# write erase boot
This command will erase the boot variables and the ip configuration of interface mgmt 0
Do you wish to proceed anyway? (y/n) [n] y
The debug option erases the debugging configuration.
switch# write erase debug
This command will erase the system only if it is set.
Do you wish to proceed anyway? (y/n) [n] y
switch# write erase poap
This command will erase the system wide POAP disable flag only if it is set.
Do you wish to proceed anyway? (y/n) [n] y
Erases configurations in persistent memory. The default action erases the startup configuration.
switch# write erase
Warning: This command will erase the startup-configuration.
Do you wish to proceed anyway? (y/n) [n] y
2) Restart the switch without saving.
switch# reload
This command will reboot the system. (y/n)? [n] y
3) Upgrade the firmware
switch# install all nxos bootflash:nxos.9.3.2.bin
Installer will perform compatibility check first. Please wait.
Installer is forced disruptive
Verifying image bootflash:/nxos.9.3.2.bin for boot variable "nxos".
[####################] 100% -- SUCCESS
Verifying image type.
[####################] 100% -- SUCCESS
Preparing "nxos" version info using image bootflash:/nxos.9.3.2.bin.
[####################] 100% -- SUCCESS
Preparing "bios" version info using image bootflash:/nxos.9.3.2.bin.
[####################] 100% -- SUCCESS
Performing module support checks.
[####################] 100% -- SUCCESS
Notifying services about system upgrade.
[####################] 100% -- SUCCESS
Compatibility check is done:
Module bootable Impact Install-type Reason
------ -------- -------------- ------------ ------
1 yes non-disruptive none
Images will be upgraded according to following table:
Module Image Running-Version(pri:alt) New-Version Upg-Required
------ ---------- ---------------------------------------- -------------------- ------------
1 nxos 9.3(2) 9.3(2) no
1 bios v07.66(06/11/2019):v07.66(06/11/2019) v07.66(06/11/2019) no
Do you want to continue with the installation (y/n)? [n] y
At this time you should answer y
Install is in progress, please wait.
Performing runtime checks.
[####################] 100% -- SUCCESS
Setting boot variables.
[####################] 100% -- SUCCESS
Performing configuration copy.
[####################] 100% -- SUCCESS
Module 1: Refreshing compact flash and upgrading bios/loader/bootrom.
Warning: please do not remove or power off the module at this time.
[####################] 100% -- SUCCESS
Install has been successful.
The switch must be reloaded another time
switch# reload
This command will reboot the system. (y/n)? [n] y
Abort Power On Auto Provisioning [yes - continue with normal setup, skip - bypass password and basic configuration, no - continue with Power On Auto Provisioning] (yes/skip/no)[no]: yes
!!! NOTE: You have selected yes option. POAP will be aborted and password configuration will be skipped !!!
Disabling POAP.......Disabling POAP
Some files need to be manually deleted, like olg logs, old firmwares.
switch# dir
4096 Nov 03 00:46:25 2021 .rpmstore/
4096 Jun 26 03:04:14 2020 .swtam/
92685 Aug 03 07:12:34 2020 20200803_070341_poap_3487_init.log
190442 Aug 04 06:19:52 2020 20200804_061119_poap_3482_init.log
28508 Nov 17 01:35:43 2021 20211117_013451_poap_3619_init.log
1777998029 Jun 26 03:01:40 2020 aci-n9000-dk9.14.1.2g.bin
0 Oct 29 02:55:59 2020 bootflash_sync_list
4096 Jun 26 02:57:34 2020 home/
4096 Nov 03 00:42:09 2021 lost+found/
1414403072 Jun 26 02:57:33 2020 nxos.9.3.2.bin
0 Aug 04 06:20:12 2020 platform-sdk.cmd
7802 Aug 04 06:19:25 2020 poap_retry_debugs.log
4096 Jun 26 03:04:44 2020 scripts/
4096 Nov 03 00:50:19 2021 virt_strg_pool_bf_vdc_1/
4096 Nov 03 00:49:54 2021 virtual-instance/
59 Nov 03 00:49:44 2021 virtual-instance.conf
Usage for bootflash://
3427209216 bytes used
50159116288 bytes free
53586325504 bytes total