Purpose

This article will explain two different methods of creating issues in multiple projects while only defining 1 mail server in Jira. The first method is specifically for Gmail making use of POP3 and the second is usable for any IMAP mail server.

Solution

Method 1:
This method requires configuration of POP3 mail accounts under a Gmail account. Each project on the JIRA Cloud application where you want to have issue creation and commenting through email available will require a separate email address configured under the Gmail account. Please be aware that there is a maximum amount of POP3 accounts that can be added under a Gmail account.

1. Setup a mail server using Gmail POP3 or IMAP as detailed in Creating issues and comments from email.
2. In the Gmail account configured in step 1, go to Settings -> Accounts and Import -> Add a POP3 mail account you own. Here you can add POP3 mail accounts to the Gmail account to retrieve mail. Add the accounts you want to use for the various projects you want to include in this configuration.
3. Now configure mail handlers using the previously added server. Point each handler towards the appropriate project, and add the email relevant to that project in the "Catch email address" box. This is further detailed in Creating issues and comments from email.
4. Repeat steps 1-3 for each project on your instance to which you want to have Issue creation and commenting through email available.

Method 2:
This method requires to create labels and mail rules under the Gmail account. Each project on the instance that you want to have Issue creation and commenting through email available will require a separate folder and fitting mail rules under the Gmail account. All project will use the same Gmail account to send their issue creation/commenting requests to.

1. Create a label for each project to which you want to have Issue creation and commenting through email available under your Gmail account. Google's documentation on this is Gmail - Using Labels.
2. Create filters to label the mails you want to relate to your projects. Refer to Gmail - Using Filters.
3. Setup a mail server using Gmail IMAP (Do not use POP).
4. Configure mail handlers using the previously added server. In the first screen, under the "Folder Name" box, define the label created in step 1 relevant to the project you are creating the handler for, and proceed configuring the handler accordingly.
5. Repeat step 1-4 for each project on your instance to which you want to have Issue creation and commenting through email available.