Re: [9fans] /n/sources/patch/spamhaus

2008-05-14 Thread Russ Cox
> for me, there's one problem with this alternative to > the "stupid" spamhaus solution — it requires i run > a linux server. It does not. There are content-based filters for Plan 9. Or I bet you could port many of the standard Unix ones over without much trouble. Mail Avenger is a little harder

Re: [9fans] /n/sources/patch/spamhaus

2008-05-14 Thread erik quanstrom
> I don't have a false positive mailbox to skim. > I run Mail Avenger, which lets me run shell scripts [...] > I run Spam Assassin. If SA thinks the mail is spam, > SMTP rejects it rather than saving it or deciding to > reject it later and having to send a bounce. That for me, there's one proble

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread Nate S
On Tue, May 13, 2008 at 4:07 PM, erik quanstrom <[EMAIL PROTECTED]> wrote: > > at work we have a barracuda box which seems to > be completely content based. it's false positive > rate is significant. so you actually need to skim > up to a hundred questionable messages per week. > more troubl

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread Russ Cox
My mail server does not run Plan 9, so my own setup would require some implementation work, as I mentioned before. > how do you maintain content-based filtering without > spending time on it on a regular basis? I typically see one or two spams a day that make it through, and I save those into a

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread erik quanstrom
>> your solution for backscatter is a good one. but >> how does it do against non backscatter? this >> is also a significant problem. generally >100 >> messages per day for me. > > content-based filtering works fine for me. how do you maintain content-based filtering without spending time

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread Russ Cox
> your solution for backscatter is a good one. but > how does it do against non backscatter? this > is also a significant problem. generally >100 > messages per day for me. content-based filtering works fine for me. > am i an idiot for objecting to this? i never said you were an idiot. i

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread erik quanstrom
> I use Greylisting [1], and it's been really effective. No false > positives (so far), and 0 to 2 spam messages a day. All this for a > mild ~15 minute delay on genuine emails (but only for the first time). sites like plan9.bell-labs.com tend not resend email with prec. bulk even when given

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread Anant Narayanan
On 13-May-08, at 4:17 AM, erik quanstrom wrote: what's a better idea. having an extra 6400 spam emails is the problem. how to i solve this without using spamhaus? I use Greylisting [1], and it's been really effective. No false positives (so far), and 0 to 2 spam messages a day. All this for

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread erik quanstrom
> So you're blocking mail from forsyth in order > to block spam bounces from <>? > > I already told you how I solved this when it > happened to me, and it has been 100% effective your solution for backscatter is a good one. but how does it do against non backscatter? this is also a significant

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread Russ Cox
> the problem is that spf only validates that the sender is an > allowed sender. this is ineffective against backscatter > attacks. i've gotten as many as 500 backscatter spam in 4 hrs. > so this is a significant issue for me. So you're blocking mail from forsyth in order to block spam bounces f

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread Wes Kussmaul
Charles Forsyth wrote: this is all reminiscent of the nonsense of RFC1413 I think that people are finally ready to accept the fact that packets on the outdoor highway do not disclose the intentions of their senders and that they contain no meaningful information about the identity of their

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread a
// rfc 2317 allows arbitrary cidrs to be delegated. so far, // i've always been able to get reverse mappings set up // for static addresses. I think you've been lucky, or have been dealing with better ISPs. Apart from my home ADSL line, I share a commercial SDSL with some folks. We've got a /123

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread erik quanstrom
>> The solution for people on dynamic addresses (typically with some >> generic and non-matching PTR record, though I haven't checked yours) is >> likely to relay out through your ISP's mail server. > > because of the way the DNS is put together, PTR records cannot be relied upon. > ownership of t

Re: [9fans] /n/sources/patch/spamhaus

2008-05-13 Thread Charles Forsyth
> The solution for people on dynamic addresses (typically with some > generic and non-matching PTR record, though I haven't checked yours) is > likely to relay out through your ISP's mail server. because of the way the DNS is put together, PTR records cannot be relied upon. ownership of the DNS en

Re: [9fans] /n/sources/patch/spamhaus

2008-05-12 Thread Jason Gurtz
The botnets have ruined the sandbox forever. On 5/12/2008 18:34, Charles Forsyth wrote: > well, i'm now on the list for the simple reason that i got a different > cable modem, which prompted a new IP address. The solution for people on dynamic addresses (typically with some generic and non-matchi

Re: [9fans] /n/sources/patch/spamhaus

2008-05-12 Thread erik quanstrom
i agree that spamhaus is a big hammer. i'm open to suggestions. preferably ones that do not require daily maintence. > Things like SPF don't catch as much spam (yet; it'll improve as the > acceptance improves), but have a very attractive false hit rate. the rate just isn't good enough for me. h

Re: [9fans] /n/sources/patch/spamhaus

2008-05-12 Thread erik quanstrom
> please don't, or at least check spf before spamhaus. > the quality of their data is at best questionable, > and there is no (usable) way to correct it. the problem is that spf only validates that the sender is an allowed sender. this is ineffective against backscatter attacks. i've gotten as m

Re: [9fans] /n/sources/patch/spamhaus

2008-05-12 Thread a
// Althrought I'd like it to be different, blacklists are quite effective // blocking spam. It's the best solution as long as we continue using SMTP. This entirely depends how you prioritize things. If "best" and "effective" are measured on what percentage of spam emails get blocked, yes, service

Re: [9fans] /n/sources/patch/spamhaus

2008-05-12 Thread Armando Camarero
was: Mon May 12 21:57:03 BST 2008 connect to net!quanstro.net: 554 5.7.1 rejected: spamhaus: sh policy ===> 2/ (message/rfc822) [inline] To: [EMAIL PROTECTED] Subject: re: [9fans] /n/sources/patch/spamhaus From: Charles Forsyth <[EMAIL PROTECTED]> Date: Mon, 12 May 2008 21:56:46 +0100

Re: [9fans] /n/sources/patch/spamhaus

2008-05-12 Thread erik quanstrom
ailed (code smtp 2838130: > Permanent Failure). > The symptom was: > > Mon May 12 21:57:03 BST 2008 connect to net!quanstro.net: > 554 5.7.1 rejected: spamhaus: sh policy > > ===> 2/ (message/rfc822) [inline] > To: [EMAIL PROTECTED] > Subject: re: [9fans] /n/sources/patch/spamh

Re: [9fans] /n/sources/patch/spamhaus

2008-05-12 Thread Charles Forsyth
CTED] Subject: re: [9fans] /n/sources/patch/spamhaus From: Charles Forsyth <[EMAIL PROTECTED]> Date: Mon, 12 May 2008 21:56:46 +0100 > what leads you to say spamhaus's data is questionable? well, i'm now on the list for the simple reason that i got a different cable modem, which prompted a new IP address.

Re: [9fans] /n/sources/patch/spamhaus

2008-05-12 Thread Charles Forsyth
> the quality of their data is at best questionable, as is their rationale

[9fans] /n/sources/patch/spamhaus

2008-05-12 Thread Charles Forsyth
please don't, or at least check spf before spamhaus. the quality of their data is at best questionable, and there is no (usable) way to correct it.