Junk Filter snags, workarounds


#1

Can anyone add to/improve on the workarounds for the Junk Filter snags below? Thanks.

  • Snag: filter overlooks mail forwarded from a DH domain
    Workaround: forward out of DH and then back in

  • Snag: filter’s quarantine is inaccessible to POP3/IMAP mail clients
    Workaround: forward using webmail, but fails to preserve header

  • Snag: filter cannot be configured by administrator without user mailbox password
    Workaround: none?

  • Snag: filter ignores mail received by catch-all addresses
    Workaround: none?

  • Snag: filter sometimes? delays messages for >=30min
    Workaround: none?

  • Snag: filter ignores some? mail originating from DH users
    Workaround: none?


#2

Here are my comments:

  • Snag: filter overlooks mail forwarded from a DH domain
    Workaround: enable junk filter on that DH domain, too.

  • Snag: filter’s quarantine is inaccessible to POP3/IMAP mail clients
    Workaround: Don’t use the junk filter and let the mail client handle all junk mail. Mozilla Thunderbird does this well but I would recommend staying with the DH junk filter + periodic use of webmail to check the quarantine list.

  • Snag: filter cannot be configured by administrator without user mailbox password
    Workaround: agree: none?

  • Snag: filter ignores mail received by catch-all addresses
    Workaround: This is deliberate by DH. You can’t use junk mail filter on a domain that has catch-all enabled due to the obscene amount of junk arriving at catch-all addresses. Workaround: Stop using catch-all addresses!

  • Snag: filter sometimes? delays messages for >=30min
    Workaround: I haven’t experienced this. No comment.

  • Snag: filter ignores some? mail originating from DH users
    Workaround: I haven’t experienced this. No comment.

TorbenGB
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#3

[quote]* Snag: filter overlooks mail forwarded from a DH domain
Workaround: enable junk filter on that DH domain, too.

[/quote]

Won;t that put the config and quarantine on the wrong domain e.g. inaccessible to the mail user?

[quote]* Snag: filter’s quarantine is inaccessible to POP3/IMAP mail clients
Workaround: Don’t use the junk filter…

[/quote]

:wink:

[quote]* Snag: filter ignores mail received by catch-all addresses
Workaround: … Stop using catch-all addresses!

[/quote]

Darn these pesky users, wanting to use the Junk Filter on the addresses that get most junk! :wink:

Thanks Torben.


#4

[quote]* Snag: filter overlooks mail forwarded from a DH domain

[/quote]

It does?

[quote]Snag: filter’s quarantine is inaccessible to POP3/IMAP mail clients
Workaround: forward using webmail, but fails to preserve header

[/quote]

Well I’m not sure what your workaround does (and you can forward messages with headers intact in webmail if you forward as message/rfc822 attachments), but I would suggest a couple of better workarounds…

  1. Use tag-only and use procmail or client-side filters to divert spam to a different IMAP folder
  2. If messages are quarantined but shouldn’t be, move them to your inbox (already possible).

Forcing people to use a relatively safe (doesn’t render images or attachments) interface to view spam and viruses isn’t just a “snag” - it’s actually intentional.

[quote]Snag: filter ignores mail received by catch-all addresses

[/quote]

Actually, as far as I know, you still can’t enable the filter at all on domains with catch-alls. That’s been discussed already.

[quote]Snag: filter ignores some? mail originating from DH users

[/quote]

I wouldn’t really consider this a snag. If you’re seeing spam that’s actually originating from another DH user (and doesn’t just appear to be), send a copy to abuse@dreamhost.com with full headers, and we’ll be happy to look at it and take appropriate action. Has this really been a big problem?


#5

It does?
[/quote]

Here yes, and Support have confirmed this is expected.

[quote]you can forward messages with headers intact in webmail if you forward as message/rfc822
[/quote]

Thats doesn’t preserve the header. From:, To: etc. are changed.

[quote]1) Use tag-only and use procmail or client-side filters to divert spam to a different IMAP folder
[/quote]

Good suggestion, thanks. I wonder if the Filter and Spam filters will work on JF tags? I’ll try it.

  1. If messages are quarantined but shouldn’t be, move them to your inbox (already possible).
    Indeed. Thanks.

[quote]Forcing people to use a relatively safe… interface … isn’t just a “snag” - it’s actually intentional.
[/quote]

I do hope not. As an alternative to a safe offline client, it’s security is false, since it doesn’t protect against false negatives. And as an addition to a safe offline client, it’s security is redundant. Against which there is the insecurity it inflicts by increasing cost of quarantine checking.

I wouldn’t really consider this a snag. If you’re seeing spam that’s actually originating
from another DH user…
[/quote]

I wasn’t referring to specifically (what DH defines as) spam, but rather to anything the config says is ‘junk’.


#6

Thats doesn’t preserve the header. From:, To: etc. are changed.

[/quote]

Not true. You can open each Message/rfc822 attachment in almost any email client and reply to it… The original message is completely unmodified.


#7

[quote]use the Junk Filter on the addresses that get most junk
[/quote]

I understand the sarcasm, but you have a good point. If you get lots of junk mail on your catch-all, but you want to keep using it, you can’t use the junk filter. BUT you can turn off the catch-all and create only those addresses that you need, and THEN you can benefit from the junk filter!

TorbenGB
Try out DreamHost with a free WebIDPrices, options


#8

Not true.

[/quote]

True. E.g. before forwarding, the header field is From: fred ; after forwarding by me it is From: me.

[quote]You can open each Message/rfc822 attachment in almost any email client and reply to it…

[/quote]

Well yes, but that doesn’t help the client itself e.g. display the original header fields, match them in filtering rules etc.


#9

Point taken Torben, but that presumes that the “addresses one needs” are known in advance - moreover one hour or more in advance, given the DH Create Address delay.

For example many use addresses of the form "providersdomain@mydomain.com" when signing-up for services on web sites so to tag the received mail for abuse monitoring or filtering. Without a catch-all address, this requires the extra work of creating the address in the DH panel and waiting for it to activate.


#10

I assumed you would know what addresses you use … I’m sure you know that catch-alls attract way too much unwanted junk, so that’s a perfectly fine reason for why you can’t have a junk filter and a catch-all at the same time.

If you need throw-away addresses for one-time use, you should check out DreamHost’s http://spam.la solution. If you need throw-away addresses for repeated use, you should check out other options such as the “dedicated” and “throwaway” solutions described here: http://g-b.dk/bin/view/Main/SpamMail#Dedicated_addresses

TorbenGB
Try out DreamHost with a free WebIDPrices, options


#11

[quote]I assumed you would know what addresses you use …
[/quote]

Even if I do, I cannot know what addresses the /senders/ use.

[quote]I’m sure you know that catch-alls attract way too much unwanted junk
[/quote]

I do not. Perhaps because I don’t know what you mean by “way too much”. I do get lots of junk through some catch-alls, but since there’s a good junk filter at the email client, it is certainly not “way too much” for me.

[quote]so that’s a perfectly fine reason for why you can’t have a junk filter
and a catch-all at the same time.

[/quote]

I really hope not… because by that token, if a single address gets as much junk, will DH disallow the JF on that too?


#12

Even if I do, I cannot know what addresses the /senders/ use.
[/quote]

I don’t understand you. Surely you provide an address to the sender which the sender then uses? Otherwise how would he send to you? Then you must know what address it is?

[quote]“way too much”
[/quote]

There are many spams being seing to random addresses, like abxgrf43@(your domain here). When you use a catch-all, you also get all of these spams, which would put a heavy load on the junk mail filter for no purpose. If you don’t use catch-all but only explicitly known addresses, then whatever is sent to your specific addresses of course needs to be filtered - regardless how large amounts of spam it gets.

TorbenGB
Try out DreamHost with a free WebIDPrices, options


#13

[quote]I don’t understand you. Surely you provide an address to the sender which the sender then uses?

[/quote]

Not necessarily. Email leaves sender free to send to anything@domain.com including any number of info@, jobs@, unforseen@ etc. and though some receivers may not want these, some may and some do.

If the receiver could practially foresee and list every future address, DH would surely not have provided the catch-all facility in the first place.

… a heavy load on the junk mail filter

[/quote]

OK, so by “way too much” you mean “way to much processing for the junk filter”. Fair point, but a worrying one, since JF can get just as much load from a regular address e.g. one to which catch-all has been routed outside DH to overcome the no-catch-all restriction. It might have been smarter for DH to leave JF in beta until able to deliver a version compatible with the pre-existing mail feauture set.

[quote]for no purpose.

[/quote]

There’s purpose - to use the catch-all feature DH have provided and promoted.