Re: [Mailman-Developers] MM3: list disabling/enabling?
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Bouncing certainly is suboptimal, since it may create collateral spam. Better to reject the message at SMTP time with a 5xx response than to bounce.
However, it's probably possible to do what you want by putting the list on emergency moderation, and changing the message, is it not? Or something similar?
If that is possible, then what's required is simply a web interface to simplify that process.
-- Ian Eiloart Postmaster, University of Sussex +44 (0) 1273 87-3148
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On Jul 12, 2011, at 01:06 PM, Ian Eiloart wrote:
Bouncing certainly is suboptimal, since it may create collateral spam. Better to reject the message at SMTP time with a 5xx response than to bounce.
That's an interesting take on it. The LMTP server in Mailman could reject messages addressed to disabled lists, and that 5xx error should propagate through the MTA.
-Barry
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- Barry Warsaw <barry@list.org>:
Is disabling a list a temporary measure? If it is, should the server reply a temporary error?
421 <domain> Service not available, closing transmission channel
(This may be a reply to any command if the service knows it
must shut down)
450 Requested mail action not taken: mailbox unavailable
(e.g., mailbox busy)
Or is it permanent?
550 Requested action not taken: mailbox unavailable
(e.g., mailbox not found, no access, or command rejected
for policy reasons)
p@rick
-- state of mind () Digitale Kommunikation
Franziskanerstraße 15 Telefon +49 89 3090 4664 81669 München Telefax +49 89 3090 4666
Amtsgericht München Partnerschaftsregister PR 563
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On Tue, 2011-07-12 at 17:23 +0200, Patrick Ben Koetter wrote:
Is disabling a list a temporary measure? If it is, should the server reply a temporary error?
In my humble opinion, an intentionally disabled list should cause the mail system to generate a 500 class error (permanent error). 400 class errors (temporary errors) are generally reserved for situations where the _intention_ is that the mail should go through but is prevented from doing so by problems for which a solution is in progress. A 400 class error causes the originating system to cache and re-try delivery, so if a list returns a 400 class error, it's just "delayed", not truly "disabled". This may be a fine distinction, and if a list is disabled for technical reasons with the intention of bringing it back up in short order without losing traffic, then perhaps a 400 class error would be more appropriate.
-- Lindsay Haisley | "We have met the enemy, and it is us." FMP Computer Services | 512-259-1190 | -- Pogo http://www.fmp.com |
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- Lindsay Haisley <fmouse@fmp.com>:
ACK. Looking at the available codes I guess the best return code would probably be 550:
550 Requested action not taken: mailbox unavailable (e.g., mailbox not found, no access, or command rejected for policy reasons)
<http://www.rfc-editor.org/rfc/rfc5321.txt, section 4.2.3. Reply
Codes in Numeric Order>
p@rick
-- state of mind ()
Franziskanerstraße 15 Telefon +49 89 3090 4664 81669 München Telefax +49 89 3090 4666
Amtsgericht München Partnerschaftsregister PR 563
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On Jul 12, 2011, at 08:52 PM, Patrick Ben Koetter wrote:
That would be my preference too. I recently had a use case for something like this. The import-sig on python.org was retired a few years ago, but I just resurrected it for the PEP 382 discussion. I probably would have used this feature for these sigs.
It does lead me to think that "retired" might be a better term, and it makes me wonder whether actions like subscribing to a retired list would still be allowed.
But maybe the OP has a different use case in mind and we could have a need for both a long-term, permanently failing retired lists, and shorter term, temporarily failing disabled lists.
-Barry
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Barry Warsaw writes:
I don't really understand under what circumstances a list owner would want to disable the *whole list* and at the same time leave retries up to arbitrary MTAs out on the Internet. The poster may or may not get a DSN. Etc, etc.
OTOH, I can imagine that for some purposes you might want a different status code, and I don't see any good reason for making that configurable and then restricting it to 5xx. Rather, document it as "this SHOULD be a 5xx code (in the RFC 2119 sense, ie, with sufficient reason it could be a 4xx code, but we don't know of any examples offhand :-)."
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On Jul 13, 2011, at 01:34 PM, Stephen J. Turnbull wrote:
I agree. I think I like the term "retire" better than "disable" to more clearly designate a step in a list's life between active and deleted.
A retired list would still exist, and people could (maybe?) still subscribe to it, etc. I think the core wouldn't treat retired lists much different than active lists except to either omit its aliases from regeneration, or give the appropriate LMTP code. One thing to think about is how MTAs like Exim will work since they don't use an alias file.
Do you really think it needs to be configurable? I mean, if we can't think of a reason to not make it 5xx, why not just wait for the first wishlist bug report? :)
-Barry
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- Barry Warsaw <barry@list.org>:
A configurable reply could provide a hint along the 550 like this:
550 See: http://list.example.com/550/listname
The listname ressource could inform why the list was retired e.g. because it was relocated or closed or where to find the retired lists archives ...
p@rick
-- state of mind ()
Franziskanerstraße 15 Telefon +49 89 3090 4664 81669 München Telefax +49 89 3090 4666
Amtsgericht München Partnerschaftsregister PR 563
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On 16 Jul 2011, at 07:18, Stephen J. Turnbull wrote:
Sure, 550 is appropriate, but an rfc1893/2034 enhanced error code should be used, too. These might be useful:
X.1.0 Other address status X.1.6 Destination mailbox has moved, No forwarding address X.2.1 Mailbox disabled, not accepting messages
Also, there's a case for customising the text returned, if not the error code.
-- Ian Eiloart Postmaster, University of Sussex +44 (0) 1273 87-3148
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On 12 Jul 2011, at 16:11, Barry Warsaw wrote:
Yes, this should be used in combination with a call forward from the MTA at RCTP TO, so that it the MTA can determine the status of the mailing list *before* giving a reply to the sending MTA.
-- Ian Eiloart Postmaster, University of Sussex +44 (0) 1273 87-3148
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On Jul 12, 2011, at 01:06 PM, Ian Eiloart wrote:
Bouncing certainly is suboptimal, since it may create collateral spam. Better to reject the message at SMTP time with a 5xx response than to bounce.
That's an interesting take on it. The LMTP server in Mailman could reject messages addressed to disabled lists, and that 5xx error should propagate through the MTA.
-Barry
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- Barry Warsaw <barry@list.org>:
Is disabling a list a temporary measure? If it is, should the server reply a temporary error?
421 <domain> Service not available, closing transmission channel
(This may be a reply to any command if the service knows it
must shut down)
450 Requested mail action not taken: mailbox unavailable
(e.g., mailbox busy)
Or is it permanent?
550 Requested action not taken: mailbox unavailable
(e.g., mailbox not found, no access, or command rejected
for policy reasons)
p@rick
-- state of mind () Digitale Kommunikation
Franziskanerstraße 15 Telefon +49 89 3090 4664 81669 München Telefax +49 89 3090 4666
Amtsgericht München Partnerschaftsregister PR 563
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On Tue, 2011-07-12 at 17:23 +0200, Patrick Ben Koetter wrote:
Is disabling a list a temporary measure? If it is, should the server reply a temporary error?
In my humble opinion, an intentionally disabled list should cause the mail system to generate a 500 class error (permanent error). 400 class errors (temporary errors) are generally reserved for situations where the _intention_ is that the mail should go through but is prevented from doing so by problems for which a solution is in progress. A 400 class error causes the originating system to cache and re-try delivery, so if a list returns a 400 class error, it's just "delayed", not truly "disabled". This may be a fine distinction, and if a list is disabled for technical reasons with the intention of bringing it back up in short order without losing traffic, then perhaps a 400 class error would be more appropriate.
-- Lindsay Haisley | "We have met the enemy, and it is us." FMP Computer Services | 512-259-1190 | -- Pogo http://www.fmp.com |
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- Lindsay Haisley <fmouse@fmp.com>:
ACK. Looking at the available codes I guess the best return code would probably be 550:
550 Requested action not taken: mailbox unavailable (e.g., mailbox not found, no access, or command rejected for policy reasons)
<http://www.rfc-editor.org/rfc/rfc5321.txt, section 4.2.3. Reply
Codes in Numeric Order>
p@rick
-- state of mind ()
Franziskanerstraße 15 Telefon +49 89 3090 4664 81669 München Telefax +49 89 3090 4666
Amtsgericht München Partnerschaftsregister PR 563
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On Jul 12, 2011, at 08:52 PM, Patrick Ben Koetter wrote:
That would be my preference too. I recently had a use case for something like this. The import-sig on python.org was retired a few years ago, but I just resurrected it for the PEP 382 discussion. I probably would have used this feature for these sigs.
It does lead me to think that "retired" might be a better term, and it makes me wonder whether actions like subscribing to a retired list would still be allowed.
But maybe the OP has a different use case in mind and we could have a need for both a long-term, permanently failing retired lists, and shorter term, temporarily failing disabled lists.
-Barry
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Barry Warsaw writes:
I don't really understand under what circumstances a list owner would want to disable the *whole list* and at the same time leave retries up to arbitrary MTAs out on the Internet. The poster may or may not get a DSN. Etc, etc.
OTOH, I can imagine that for some purposes you might want a different status code, and I don't see any good reason for making that configurable and then restricting it to 5xx. Rather, document it as "this SHOULD be a 5xx code (in the RFC 2119 sense, ie, with sufficient reason it could be a 4xx code, but we don't know of any examples offhand :-)."
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On Jul 13, 2011, at 01:34 PM, Stephen J. Turnbull wrote:
I agree. I think I like the term "retire" better than "disable" to more clearly designate a step in a list's life between active and deleted.
A retired list would still exist, and people could (maybe?) still subscribe to it, etc. I think the core wouldn't treat retired lists much different than active lists except to either omit its aliases from regeneration, or give the appropriate LMTP code. One thing to think about is how MTAs like Exim will work since they don't use an alias file.
Do you really think it needs to be configurable? I mean, if we can't think of a reason to not make it 5xx, why not just wait for the first wishlist bug report? :)
-Barry
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- Barry Warsaw <barry@list.org>:
A configurable reply could provide a hint along the 550 like this:
550 See: http://list.example.com/550/listname
The listname ressource could inform why the list was retired e.g. because it was relocated or closed or where to find the retired lists archives ...
p@rick
-- state of mind ()
Franziskanerstraße 15 Telefon +49 89 3090 4664 81669 München Telefax +49 89 3090 4666
Amtsgericht München Partnerschaftsregister PR 563
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On 16 Jul 2011, at 07:18, Stephen J. Turnbull wrote:
Sure, 550 is appropriate, but an rfc1893/2034 enhanced error code should be used, too. These might be useful:
X.1.0 Other address status X.1.6 Destination mailbox has moved, No forwarding address X.2.1 Mailbox disabled, not accepting messages
Also, there's a case for customising the text returned, if not the error code.
-- Ian Eiloart Postmaster, University of Sussex +44 (0) 1273 87-3148
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On 12 Jul 2011, at 16:11, Barry Warsaw wrote:
Yes, this should be used in combination with a call forward from the MTA at RCTP TO, so that it the MTA can determine the status of the mailing list *before* giving a reply to the sending MTA.
-- Ian Eiloart Postmaster, University of Sussex +44 (0) 1273 87-3148
participants (5)
-
Barry Warsaw
-
Ian Eiloart
-
Lindsay Haisley
-
Patrick Ben Koetter
-
Stephen J. Turnbull