Hi,
Wouldn't it make sense to define a default for maxmessagesize with areasonable value, like 100m or so? I mean just to make broken clientshappy :)
I thought this was already updated in 3.6, but it looks like it's only on 3.8 (which should get a stable release very soon)...
Here's the imapd.conf(5) man page from 3.8 (emphasis mine):
maxmessagesize: 0Maximum size of messages that will be accepted by Cyrus. This affects LMTP deliveries, IMAP appends, DAV uploads, etc. Messages larger than this will be rejected.If set to 0 (the default), a large internally-defined limit will be applied.If no unit is specified, bytes is assumed.
As noted earlier in the discussion, APPENDLIMIT reports the maxmessagesize. In 3.6 and earlier, maxmessagesize: 0 (the default) meant unlimited, which on 64-bit systems meant "the largest 64-bit value (ish)", which is obscenely large -- like, petabytes or something. So if you have your 64-bit server configured to allow unlimited message sizes, and your version reports APPENDLIMIT, you'll get this big number in the APPENDLIMIT line.
From 3.8 on, there will be no such thing as "unlimited" anymore. A maxmessagesize of 0 (the default) instead sets a limit that is very high but won't overflow an int. (On a 64-bit system, you will be able to manually set a maxmessagesize that is larger than the one you would get by using 0, but it's still not "unlimited" and doesn't pretend to be, and if you do this and it breaks you get to keep the pieces.)
Regardless, you really ought to choose, and then configure, a maximum message size that you're willing to support (consider your network, system memory, filesystem limits, hot storage, backup storage, log storage, expected usage, user trust, etc...). Cyrus can't do this for you, it doesn't know your intentions.
Cheers,
ellie
