Laura,
Thanks for your question. First of all, if you are not receiving the support you need in your case, please request to have it escalated or for a Manager review. This will make sure your questions are answered.
Regarding Firmware upgrades, there are three main methods:
- In Service Software Upgrade (ISSU) when going from one minor release to another. This is a non intrusive, warm reload of the VDX and can be completed on an whole fabric without losing traffic.
- Cold Boot, when going between major releases. This requires the VDX to be fully reloaded and causes a traffic interruption
- Default-Config, when making large jumps in major releases. This is a preferable option when you have a smaller config and are looking to save time with an upgrade that would require multiple steps.
Depending on your design the order in which you complete your upgrade can change. Normally with dual homed hosts in Data Centers we recommend using the "Odd Even" approach.
When using this approach, you should not lose management access to the devices, the Management network is independent of the VCS fabric and would be reachable even if all the devices are segmented.
Regarding compatible versions, a VCS fabric will only form if all devices are on the same version, so with this said, when completing the Odd/Even approach we recommend to fully upgrade the Odd side (excluding your Principle switch), then upgrade your Even side (excluding your Principle switch) and then finally upgrading the Principle last.
For the actual Firmware Download command. I would recommend you use the "interactive" option. The VDX will prompt you for all the necessary options.
- firmware download interactive
I hope I covered all of your questions, or at least gave you some clarity. Please also review our KB article for Best Practices when completing a Firmware Upgrade:
https://gtacknowledge.extremenetworks.com/articles/Solution/NOS-Firmware-Upgrade-Best-Practices
And if you need anything further, please do not hesitate to escalate your case and we can discuss further.
Thanks,
Mike Morey
Principal Technical Support Engineer
Michael Morey
Principal Technical Support Engineer
Extreme Networks