I’ve been superbusy with upgrading a customer infrastructure and i have some interesting conclusions:
- nexuses are scary to upgrade. Be prepared to do a manual module reload, to have to wait hours for them to wake up, be prepared for the worst case scenario
- always, always, always read the release notes. For example, did you know that an upgrade from 6.1 to 6.2 on a nexus 7010 sup 1 needs a memory upgrade to 8gb? Well, nor did I. And Cisco actually let me initiate the installation!!! that was well scary.
- slashes count. While verify /md5 bootflash://mynewimage.bin may work, boot system flash bootflash://mynewimage.bin will cause a supervisor crash. Make sure there are no slashes in the path.
- always have remote hands in case something goes wrong. A supervisor may need to be reinserted, anything can go wrong
- after an upgrade weird things can start happening. Crashes, dot1x failures, phones stop working etc etc. Come to work extra early following a weekend upgrade.
- make sure your clients can authenticate with dot1x; this involves having some ppl around on the upgrade day who can test things
- printers are crazy. Get some ppl to do test prints on all the printers after the upgrade. Get them to send an email to you that they did
and despite all that, there will be blood….