I want to migrate project data from JIRA v3.10 to JIRA v6.4.9.
In that JIRA v3.10 i have test steps and expected result.
so i want to know what is best way to migrate? should i first upgrade JIRA from 3.10 to 6.4.9 but it will take so much time because i have to go step by step means first need to upgrade to 4 , 5 then 6
Or Should i migrate issue using CSV import? but int that how do i move the attachment and test steps and expected result.