[Mailman-Users] large list questions (15000 users)

[Jon Carnes]

On Mon, 2002-09-02 at 10:22, Lars Andersson wrote:
> I've been using mailman for my private small lists for a while now and I
> am very pleased with it. Now it's time to sneek it into my work.
> 
> I'm working for a webhosting company and a customer wants me to
> implement a list with around 15.000 recipients. The list will be used
> for a daily post from the administrator to the recipents, so the traffic
> will be fairly limited and controlled. I have a few questions.
> 
> 1. Can mailman handle such large lists (It will be running on a
> dedicated linux box with postfix on the localhost as MTA). Of course
> with SCSI, raid, plenty of ram etc.

Yes.

> 
> 2. Is there a simple way to limit what the administrator of a list can
> change when he is administering a list? For example, I don't want him to
> be able to change the max post size for mailinglist.

Not in the current release version, but there are work-arounds if you
have access to root (or the user mailman) on the system. Basically, you
can write a cron job to examine the list and email you with any
configuration changes to the list. You can also have the cron job reset
the list with the base saved configuration.  

None of that is standard with Mailman. You will have to write scripts
using the Command Line Interface commands that come with Mailman.

> 
> 3. If he uses the web interface to handle his list, does it scale up to
> 15.000 users?

Yes.  The main gotcha here is having a slow Disk Subsystem, but since
you are SCSI it will probably not be an issue. A secondary gotcha is not
having enough RAM, but you mention that the server has plenty.

> 
> 4. Is there any other problems running such a big list that I should be
> aware of before I go ahead and implement the list.

Changes to the list membership may take a bit of time.  This is very
dependent on how fast your Disk subsystem is and on how much RAM you
have to cache read/writes.  If the time grows too long (which it should
not for 15k) then you may need to split the list into smaller lists or
consider running a RAM disk (using some of your RAM) and loading the
configuration files for the list onto the RAM disk.

This is a standard work-around for folks with exceptionally large lists
running the current version of Mailman.  It works very well.  But with
only 15k and a decent disk subsystem, you should not see dramatic slow
downs while managing the membership lists.

BTW: the RAM disk size necessary for this is about ~50Mb (roughly twice
the size of the configuration directory).
> 
> 5. User administration.
> It would be best for me if the owner of the list could handle
> unsubscriptions by sending mail to Mailman (without knowing the password
> for the user he wants to unsubscribe). Is this possible or does he need
> to use the web interface?  I know you can do a lot of things on the
> command line and by using the web interface but this administrator wants
> to use mail for this kind of commands. It's also the fastest way when he
> has so many users.

No problem. Each list has an administrative password.  He can
unsubscribe folks via email using that password.

> 
> Thanks in advance
> 
> /Lars
> 

You're welcome.  Hope it helps!

Jon Carnes