Extended Fast Software Upgrade (xFSU) - difference in commands?

[vv0bbLeS]

Hello all,

Per the Cisco documentation on Extended Fast Software Reload (xFSU) on 9300 switches, there are 2 commands to accomplish this "fast upgrade" process:

• install add file <image URL> activate xfsu commit (available in Cisco IOS XE 17.8 release and above)
• install add file <image URL> activate reloadfast commit (available in Cisco IOS XE 17.3 and 17.6 releases)

From reading the doc above, it looks like the xfsu upgrade command doesn't require a reload, while the reloadfast upgrade command includes a fast reload.

So, my question is:

• Why we would ever use the reloadfast upgrade command when the xfsu upgrade command doesn't require a reload?
  • Is there some part of the software upgrade process that requires a reload "at some point" in order for the software upgrade to be considered "100% complete" ? (i.e. we run the xfsu command with no reload, and then later we can separately run the plain reload fast command to do a fast reload?)

[Reza Sharifi]

Hi,

I have not tested this, but if I am reading the document correctly, you still need a "reload fast" in order for the new software to be active.

HTH 

[Leo Laohoo]

Make sure TAC is on the phone or WebEx into this switch when performing FSU/eFSU/xFSU because this is no different to ISSU where ISSU &/or FSU/eFSU/xFSU only works in "corner cases" or in a lab or demo.  ISSU &/or FSU/eFSU/xFSU is not known to work well in production.  

We tried eFSU on a stack of 9300 and it crashed the master.