Reference Guide

Table Of Contents
To view the command-history trace, use the show command-history command.
Example of the show command-history Command
Dell#show command-history
[5/18 21:58:32]: CMD-(TEL0):[enable]by admin from vty0 (10.11.68.5)
[5/18 21:58:48]: CMD-(TEL0):[configure]by admin from vty0 (10.11.68.5)
- Repeated 1 time.
[5/18 21:58:57]: CMD-(TEL0):[interface port-channel 1]by admin from vty0
(10.11.68.5)
[5/18 21:59:9]: CMD-(TEL0):[show config]by admin from vty0 (10.11.68.5)
[5/18 22:4:32]: CMD-(TEL0):[exit]by admin from vty0 (10.11.68.5)
[5/18 22:4:41]: CMD-(TEL0):[show interfaces port-channel brief]by admin from
vty0
(10.11.68.5)
Upgrading and Downgrading Dell Networking OS
To upgrade or downgrade Dell Networking OS, refer to the Release Notes for the version you want to
load on the system.
Using Hashes to Validate Software Images
You can use the MD5 message-digest algorithm or SHA256 Secure Hash Algorithm to validate the
software image on the flash drive, after the image has been transferred to the system, but before the
image has been installed. The validation calculates a hash value of the downloaded image file on system’s
flash drive, and, optionally, compares it to a Dell Networking published hash for that file.
The MD5 or SHA256 hash provides a method of validating that you have downloaded the original
software. Calculating the hash on the local image file, and comparing the result to the hash published for
that file on iSupport, provides a high level of confidence that the local copy is exactly the same as the
published software image. This validation procedure, and the verify {md5 | sha256} command to support
it, can prevent the installation of corrupted or modified images.
The verify {md5 | sha256} command calculates and displays the hash of any file on the specified local
flash drive. You can compare the displayed hash against the appropriate hash published on i-Support.
Optionally, the published hash can be included in the verify {md5 | sha256} command, which will display
whether it matches the calculated hash of the indicated file.
To validate a software image:
1. Download Dell Networking OS software image file from the iSupport page to the local (FTP or TFTP)
server. The published hash for that file is displayed next to the software image file on the iSupport
page.
2. Go on to the Dell Networking system and copy the software image to the flash drive, using the copy
command.
3. Run the verify {md5 | sha256} [ flash://]img-file [hash-value] command. For example, verify sha256
flash://FTOS-SE-9.5.0.0.bin
4. Compare the generated hash value to the expected hash value published on the iSupport page.
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Getting Started