Re: [Dovecot] fallback for proxy?
On Sunday, October 28, 2007 8:32am, Cor Bosman [EMAIL PROTECTED] said: Is it possible somehow to configure a fallback for a failed proxy? I am using sql based proxying through dovecot, but it would be nice if you can fallback to another host if the proxy destination server is down. High availability and all.. We do this in our system by having a separate monitoring server update the IP in MySQL when a backend server fails. Bill
Re: [Dovecot] Dovecot strong or not for a big Webmail architecture
On Thu, August 2, 2007 3:06 pm, John fistack [EMAIL PROTECTED] said: I know webmail.us use Dovecot, what is the most big dovecot architecture known ? Do you think Dovecot can handle 1 million of active users in a good architecture ? Yep... and we have 500K very active users on it. We've scaled Dovecot horizontally without NFS, just lots of independent Dovecot server intances with smart proxy/mail-routing infrastructure around it. It can easily scale to millions of users this way. Just make sure you throw enough disks at it and you'll be fine, with or without NFS. Do you think it's a good solution to use one synchronised local Openldap on each server Dovecot ? No. I'd replicate your ldap database on a few servers that are dedicated to that purpose, and on each mail server use Dovecot's auth_cach feature to minimize how often it needs to query ldap. Do you think It's possible to use Postgresql or MySQL instead of Openldap ? We use MySQL. MySQL handles frequent writes better than OpenLDAP from our experience. It is also simpler for us to do replication and troubleshooting because we employ several MysQL gurus already. Are cyrus or courrier-imap better solutions ? Definitely not courier-imap, because of it's lack of indexes. Not sure about Cyrus. Someone say Zimbra is highly scalable and fast, I think Zimbra could be to heavy in this architecture, is Dovecot scalable ? My opinion is Zimbra is too heavy beccause of the way mail is stored on the backend. Dovecot with maildir scales out well, and the promise of dbox mail storage format appears that it will make it even more scalable down the road. Bill
Re: [Dovecot] Missing MIME-Version header in e-mails.
On Wed, August 1, 2007 8:36 pm, Tan Shao Yi [EMAIL PROTECTED] said:
Will it be possible to make this available in the 1.0 branch? UW-IMAP
seems to continue to process e-mails without the MIME-Version, so long as
it has the Content-Type or -Encoding header.
It's an easy patch if you want to apply it to your installation. Probably
something like this, although I haven't tried it...
src/lib-mail/message-parser.c @225:
- if (!hdr-eoh strcasecmp(hdr-name, Mime-Version) == 0) {
+ //if (!hdr-eoh strcasecmp(hdr-name, Mime-Version) == 0) {
/* it's MIME. Content-* headers are valid */
part-flags |= MESSAGE_PART_FLAG_IS_MIME;
- }
Re: [Dovecot] v1.1 max connections per user
On Sat, June 30, 2007 7:50 pm, Charles Marcus said:
Timo Sirainen, on 6/30/2007 7:25 PM, said the following:
On Sat, 2007-06-30 at 19:11 -0400, Charles Marcus wrote:
Timo Sirainen, on 6/30/2007 6:43 PM, said the following:
v1.1 has now:
# Maximum number of connections allowed for a user. The limits are enforced
# separately for IMAP and POP3 connections, so you can move this setting
# inside protocol {} to have separate settings for them. NOTE: The user
names
# are compared case-sensitively, so make sure your userdb returns usernames
# always using the same casing so users can't bypass this limit!
#mail_max_user_connections = 10
Is 10 a good default?
I'm assuming this is per IP?
No. I'm not sure if it should. Perhaps. It's mostly intended to prevent
unintentional abuse by stupid clients, so having 3+ thunderbirds open in
different locations with each having 5 connections should probably be
allowed.
Ok - you said 10 was the default - but then said that 15 (3 TBirds x 5)
connections should be allowed, which is more than 10... so... you just
meant that one could accommodate that by upping this limit to 15?
I like 15. That way it is high and isn't as likely to affect existing
installations unless they manually set it to something lower. Or if you want
to have a separate default for POP vs IMAP, I'd use 5 for POP and 15 for IMAP.
Re: [Dovecot] testing needed: log file concurrency
On Tue, June 19, 2007 7:41 pm, Timo Sirainen [EMAIL PROTECTED] said: http://dovecot.org/tmp/concurrency.c I'd want to know what results this program gives with different systems. Please test and reply (but don't bother if someone already replied with the same OS+result). I expect it to print: ./concurrency writing, page size = 4096 ./concurrency 1 reading, page size = 4096 Red Hat ES3 (2.4.21-32.0.1.EL) athlon i386
Re: [Dovecot] Replication plans
On Fri, May 18, 2007 1:42 am, Troy Benjegerdes [EMAIL PROTECTED] said: I'm going to throw out a warning that it's my feeling that replication has ended many otherwise worthwhile projects. Once you go down that rabbit hole, you end up finding out the hard way that you just can't avoid the stability, performance, complexity, and whatever problems. .. I've found myself pretty much in the same all roads lead to the filesystem situation. I don't want to replicate just imap, I want to replicate the build directory with my source code, my email, and my MP3 files. One of the problems with the clustered file system approach seems to be that accessing Dovecot's index, cache and control files are slow over the network. For speed, ideally you want your index, cache and control on local disk... but still replicated to another server. So what about tackling this replication problem from a different angle... Make it Dovecot's job to replicate the index and control files between servers, and make it the file system's job to replicate just the mail data. This would require further disconnecting the index and control files from the mail data, so that there is less syncing required. i.e. remove the need to check directory mtimes and to compare directory listings against the index; and instead assume that the indexes are always correct. Periodically you could still check to see if a sync is needed, but you'd do this must less frequently. I agree that there are already great solutions available for replicated storage, so this would allow us to take advantage of these solutions for the bulk of our storage without impacting the speed of IMAP. Bill
Re: [Dovecot] Replication plans
On Fri, May 18, 2007 1:10 pm, Timo Sirainen [EMAIL PROTECTED] said: On Fri, 2007-05-18 at 12:20 -0400, Bill Boebel wrote: So what about tackling this replication problem from a different angle... Make it Dovecot's job to replicate the index and control files between servers, and make it the file system's job to replicate just the mail data. This would require further disconnecting the index and control files from the mail data, so that there is less syncing required. i.e. remove the need to check directory mtimes and to compare directory listings against the index; and instead assume that the indexes are always correct. Periodically you could still check to see if a sync is needed, but you'd do this must less frequently. This would practically mean that you want either cydir or dbox storage. This kind of a hybrid replication / clustered filesystem implementation would simplify the replication a bit, but all the difficult things related to UID conflicts etc. will still be there. So I wouldn't mind implementing this, but I think implementing the message content sending via TCP socket wouldn't add much more code anymore. The clustered filesystem could probably be used to simplify some things though, such as UID allocation could be done by renaming a uid-next uid file. If the rename() succeeded, you allocated the UID, otherwise someone else did and you'll have to find the new filename and try again. But I'm not sure if this kind of a special-case handling would be good. Unless of course I decide to use the same thing for non-replicated cydir/dbox. Dbox definitely sounds promising. I'd avoid putting this uid-nextuid file in the same location as the mail storage though, because if you can truly keep mail storage isolated and infrequently accessed, then you can do cool things like store your mail data remotely on Amazon S3 or equivalent.
Re: [Dovecot] dbox redesign
On Sat, May 12, 2007 9:10 am, Timo Sirainen [EMAIL PROTECTED] said: Fast copying Would be nice if copying a message from one mailbox to another wouldn't require actually reading+writing the whole message contents. But I can't really figure out how to implement this without requiring that there is only a single dbox storage which contains the mails for all the mailboxes, and the mailboxes themselves are just Dovecot's index files containing pointers to the dbox storage. The problem with having everything in one storage is that if the index files are broken, the messages can't be placed into correct mailboxes anymore. Although one possibility would be treat mailboxes a bit similarly than keywords. So that when a message is copied to another mailbox, the message in dbox file is updated to contain information that it exists in such and such mailboxes. Hmm. Perhaps that would be good enough, yes. Yes, I think treating mailboxes similary to keywords is ideal. There really is no reason to physically separate mailboxes on disk. All that is needed is this logical separation if it can be done in a reliable way. Or maybe track this in mailbox-specific index files, and also have a corespodning text file that stores a list of messages that are contained in that mailbox... similar to maildir's dovecot-uidlist file. Then if you lose the index you can rebuild the index from the text file. Bill
[Dovecot] Sorting by Received vs Sent
Looks like in Cyrus, sorting by Received date is faster than sorting by the Sent header date because of the way they use the index and cache files... http://www.emaildiscussions.com/showpost.php?p=419246 Is this the case in Dovecot as well? Bill
Re: [Dovecot] dovecot-auth %c variable is not working
On Thu, April 19, 2007 3:23 pm, Andrey Panin [EMAIL PROTECTED] said: On 109, 04 19, 2007 at 12:17:41PM -0400, Bill Boebel wrote: In doc/variables.txt For dovecot-auth there are also these variables: %c - secured string with SSL, TLS and localhost connections. Otherwise empty. %c does not appear to be working. I am trying to use it in a MySQL query userdb and passdb query and it is always empty string. Seems like secured flag isn't passed to blocking passdb handler. Can you try attached patch ? This patch indeed fixed it. Tested with all 4 protocols... pop3 - %c = '' pop3s - %c = 'secured' imap - %c = '' imaps - %c = 'secured' Thanks Andrey! Bill
Re: [Dovecot] deliver to subfolder with dovecot's LDA
On Fri, March 16, 2007 8:12 pm, Tom Bombadil [EMAIL PROTECTED] said:
How can deliver messages to a subfolder using the LDA?
For example, I want a message to [EMAIL PROTECTED] to be placed inside
the 'spam' subfolder.
$ deliver --help
Usage: deliver [-c config file] [-d destination user] [-m mailbox]
[-f envelope sender]
So for the example above, you can call it like this:
$ deliver -d [EMAIL PROTECTED] -m spam
To do this from Postfix, /etc/postfix/master.cf:
dovecot unix - n n -- pipe
flags=DRhu user=virtual argv=/usr/libexec/dovecot/deliver -d ${recipient} -f
${sender} -m ${extension}
However, I think LDA freaks out if you pass -m . So this might not work when
there is no +folder.
Timo: Should -m treat empty string as if -m was not passed at all?
Bill
