An umbrella list is a mailing list that contains the addresses of other mailing lists instead of, or in addition to, personal email addresses. This provides for a structured way of mailing people within a department or school. Imagine a hypothetical mailing list called staff which acts as an umbrella list for other mailing lists called (say) technical-staff, clerical-staff and teaching-staff. Those three sub-lists, although independent mailing lists in their own right, would themselves contain the staff members' email addresses, though they could also act as umbrella lists to other sub-lists, in finer detail. This structure not only allows a greater degree of control over membership management, but also allows for sub-groups of staff members to be emailed separately as required.
Umbrella lists (in the Mailman system as used at EMWD) do have to be carefully configured and managed, however, and this is not a trivial undertaking. It's important that they are correctly configured so as not to behave in the same way as conventional mailing lists. The following guidelines should help if you are planning to set up a group of such Mailman-based mailing lists:
- We strongly recommend that all the mailing lists in the umbrella are configured as Private Broadcast lists, so that only the list administrator and other designated individuals are allowed to send email to the lists.
- All the mailing lists in the umbrella should have the same administrator and moderator passwords.
- All the umbrella lists need to be able to distribute email to their member lists. This means setting up all the member lists with "acceptable aliases".
- NEVER configure a mailing list as an umbrella list if it isn't actually working as an umbrella list, otherwise you'll have problems.