Sometimes, mailing list management goes out of control. Years after years people are tending to add more and more mailing lists (also known as Distribution Lists) and almost never delete the old ones. After a few years you will discover that you have more mailing lists than actual people in your organization, just as I did recently when helping a customer with some Postini troubleshooting.

The well-accepted approach for mailing list management in Postini is to add mailing list email address as an alias under some account in (i.e. This is correct for both manual management and mailing list syncing via Google Apps Directory Sync for Email Security.

This approach works well, until you want to know which mailing lists are in use and which aren't. Since all of the mailing lists are under the same account in Postini ( simple use of "Reporting" tab in Postini Console won't reveal the required information.

However, I was able to find a simple workaround which will give you a list of mailing list addresses which were actually and validly used during last 30 days (i.e. received valid email from external recipient).

This is the process:
  1. Select you Postini Account Organization (let's say "CompanyX Account")
  2. Select Log Search and fill it according to this:

Clicking "Export All" will generate a CSV file (it can be quite large, mine was 9MB).

Use your spreadsheet of choice to open the file (I used Google Spreadsheet, but you can do it with Microsoft Excel as well). The export file contains a lot of columns, but we'll need only some of them. Here is the list of the columns we are going to use:

'Direction' | 'To' | 'Disposition' | 'Disposition Filter' | 'Primary Address'

Now, we'll need to filter out some rows to get a list of only valid emails (i.e. not spam messages). Set your filters this way:

Direction = Inbound Only
Disposition Filter != "Blatant Spam Blocking" & Disposition Filter != "Virus Filtering"
Primary Address ==

The last action should be getting rid of duplicate rows (i.e. mailing lists which received an email more than once for last 30 days). Both Microsoft Excel and Google Spreadsheet provide an easy way to do it.

The resulting list is only externally used & valid mailing list addresses. All the rest isn't used anymore and you can act accordingly. 

The last thing - what to know how many aliases (i.e. mailing lists) you have under your Postini account?

Here is the simple batch command to use:

listusers ALL,, targetOrg=100046262, childorgs=1, aliases=1

The "TargetOrg" is the Postini Account Organization ID. The return values are a comma separated list of aliases for
AuthorVadim Solovey
Categoriespostini, tips