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) > >>>> 3- if you can queue mail, you can deliver it ;-p >>>> 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 > >> c-ya! >> >> Ildefonso. > >
