> On Mon, Nov 24, 2008 at 4:49 AM, mouss <[EMAIL PROTECTED]> wrote: > > Jose Ildefonso Camargo Tolosa a écrit : > > > >>> However, Postfix supports access maps that can reject mail for > >>> over-quota users, if you are willing to periodically add up all > >>> the mail each user has. > >> > >> I have been using filesystem quotas for this purpose, and it works > >> just fine. Off course, I have a "dedicated" filesystem for mail > >> storage. > >> > > > > The problem is that this is detected at delivery time, which will > cause > > backscatter if it happens too often and your filter misses a lot of > > spam. if this doesn't happen often, then yes, it's the easy way. > > otherwise, an access check as suggested by Wietse may be necessary. > > True, that's why I try to implement many "quota warning" systems, so > the user knows that he/she have to clean their mailbox, also, there is > a side-effect to the fs quota: it is pretty much likely that the imap > server (dovecot) fail to access the user mailbox once the hard limit > is over (unless you fix it, but I didn't), and they just call support, > and then one tells them to clean up the mailbox asap, and just > "reenable" the access (by deleting a couple of dovecot's files, and > extending their quota for a while). > > Well, I also try to have a good spam filter (ASSP). > > > > >>>> 2- there is no safe quota support in any MTA. most quota > implementations > >>>> will send a bounce, which may resultin backscatter > >> > >> true. but quotas are necessary: the more disk space the users have, > >> the more garbage they store. > >> > > > > but this doesn't require checking quota in real time or at delivery > > time. populating an access list (periodically or opportunistically) > > should be enough. > > maybe, but can also prove to be slow, and even more when you have > thousands of users. I think that... maybe... using soft-quotas (as a > counter) and having unlimited hard-quota and grace periods could have > a similar effect, and can be faster (I don't know if this actually > works, I hasn't tried) >
Infact, this is exactly the problem that I have. I'm using Postfix as post-office platform too. And I need to check disk usage. First time I ve patched with VDA patch. Then I have upgraded postfix and I have no more appliad the relative patch. Indeed I read that is not good to use VDA patch so I have believed that that there was a native support for quota by Postfix. Anyway I share the fact that MTA has not to face quota issues, as mouss pointed out in a previous email. But I have to check quota exactly for the same needs that you have exposed. Have you a pratical alternative to VDA patch to suggest me? > >>>> 3- if you can queue mail, you can deliver it ;-p As I just have pointed out, I'm using as Post office. > >>>> 4- disks don't cost too much now. > >> > >> true, but when you have >10k users, the cost of each "not so > >> expensive" hard drive starts to add, and not only that, in a public > >> organization you can have wait-times of around 6 months just to get > a > >> hard drive. Oh, and don't forget: you have plug these hard drives > >> somewhere: every server has they "hard drives limit", and you could > >> take a PC and lots of SATA controllers, and build a nice low-cost > >> NAS-like thing, but a few people qualify this as "unreliable", they > >> need to spend lots of money on IBM or HP storage systems, and > because > >> of the cost, they just don't buy them, and thus: we have a limited > >> amount of disk space :( . > >> > > > > Agreed. > > > >>>> 5- if your users abuse mail, destroy their heads, not ours. > >> > >> mmmm........ I don't think my boss let me do that, jejejeje :D > >> > > > > you must make it look like an accident :) > > mmmm....... jejejejeje :D > Very smart! I will try.. ;-)
