[j-nsp] upgrading M120 directly from 8.5 to 9.3

[Jared Mauch]

On Jan 11, 2010, at 3:41 PM, Brad Fleming wrote:

> My experience is to always test the upgrade on a spare device; especially if its an "unsupported" upgrade path. A similar chassis running the same config will help determine what parts of the config are likely to change. If possible, I'd suggest attaching your spare device to your in-service network and make sure services will continue to work. I know this all seems like a huge pain, but if you're anything like me you only upgrade software every couple years (unless there's a major problem).
> 
> If you don't have spare gear available, I'd suggest opening a TAC case and asking for an official, supported upgrade path using software that's available today. That way if something goes wrong, you already have a ticket open with the basic info.

+1

We asked Juniper about this and this, and I'm not sure they've released an 'official' policy around this.  I suggest following the usual standard-operational-practices and doing the following:

1) Check that your OOB works
2) Test in lab [if possible]
3) Load the code on local media (including all relevant jinstall images, including current one if you need to back-out for some unforseen reason).
4) (Some people may not like this, but ...) try jumping to the release you want directly with the jinstall.  Here's where #1 is *MOST* important!!!!

Somtimes there are some random failures, mgd issues and config hating processes.  You want to do something like:

request system software add delay-restart no-validate reboot /var/tmp/jinstall-13.0R1.tgz 

You may need to tweak your config if something 'odd' has happened between reelases, like rewriting of the way bgp or whatnot works.

You should understand that the no-validate clearly comes with caveats, but doing this should make the jump easier.

here's to improving the process and finding a document on jumping from EEOL to current software on the JTAC site..

- Jared