Upgrade from Jira 6.3.1 to Jira software risks

[Kishor R]

We are planning to upgrade from JIRA 6.3.1 to JIRA software and we have below few questions.

1. What happens to all the custom fields that we have created when we upgrade? Do they pushed to new software as is?
2. All my projects and user access rights to respective projects remain intact?
3. Existing Modules/features which will have an impact and the description of changes that can be observed?
4. What are the technical pre-requisites prior to the upgrade?. 
5. Risks that need to be handled while doing the upgrade (Impact on existing features, configurations, data etc.)

[Nic Brough -Adaptavist-]

Your data will be upgraded, including all the custom fields, users and configurations.

For details of the changes, there's no way we can tell you about the "risks" or even what might affect you directly.  You should read the release notes for each major release of JIRA between 6.3 and the version you want to land on.  (i.e. 6.4, 7.0 and 7.1 if you're heading for "latest")

[Kishor R]

Thanks for the resposne.

Could you also confirm whether

1. "All my projects and user access rights to respective projects remain intact?"
2. Existing Modules/features which will have an impact and the description of changes that can be observed?

[Nic Brough -Adaptavist-]

1. As per the first paragraph in my answer
2. As per the second paragraph in my answer

We can't tell you what might change in your system - we don't know what you've configured, what add-ons you're using and so-on.  It's something you need to work out for yourself.

[Kishor R]

Hi Nic,

1.What happens to schemes, workflow, issue types, screens and field configuration when we upgrade from JIRA to JIRA software? Do they remain intact in new version?

2. We are using Tempo(timesheet) as an add on with our current version of JIRA (6.3).

1. Does the existing setup remain intact between tempo and JIRA software when only JIRA software is upgraded? OR
2.  Do we have to manually upgrade Tempo separately after JIRA upgrade?
3. If it is yes to manual upgrade of Tempo, will the existing setting remain intact?

Thanks in advance for your help

[Nic Brough -Adaptavist-]

Same answer as before.