I'm not sure where the instructions are telling you to look for Integrations (could you link the document you're looking at please?).
https://confluence.atlassian.com/display/BitbucketServer/Linking+Bitbucket+Server+with+JIRA should help you set up the integration. Go into the admin screens (the cog in the upper right will take you there if you're an admin) in Bitbucket Server and find Application Links.
Hello! My name is Mark Askew and I am a Premier Support Engineer for products Bitbucket Server/Data Center, Fisheye & Crucible. Today, I want to bring the discussion that Jennifer, Matt, and ...
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