Geek Query - Grin with cat attached — LiveJournal
Previous Entry Next Entry
Geek Query Feb. 21st, 2006 12:15 pm
How often do you get "I can't mail this person" or "This person can't mail me" queries? ie not user error, but SMTP fuckups, DNS weirdities etc? I'm wondering if one every week or two for a 30-person company means there's an unusual degree of fubar.

ETA: I presume you all have multiple MXs?

From: d_floorlandmine
Date: February 21st, 2006 - 12:22 pm (Link)
We're about that size, and I get very few of those. That I hear about, anyway.

It may be coincidence...

From: kingginger
Date: February 21st, 2006 - 12:25 pm (Link)
...but I've found a few different companies recently have had that start happening to them...

Just occasional, but its always SMTP errors not finding the domain they are being sent to.

Only common factor I have is that BT are involved in someway usually.


Re: It may be coincidence...

From: wechsler
Date: February 21st, 2006 - 12:47 pm (Link)
Tends to be BT connect or miscellaneous vanity domains, from what I can see.

Re: It may be coincidence...

From: azekeil
Date: February 21st, 2006 - 12:57 pm (Link)
Sounds like some RBLs are being used somewhere which dislike DSL servers.

Re: It may be coincidence...

From: dennyd
Date: February 21st, 2006 - 01:01 pm (Link)
The largest RBL added all BT's static IP blocks to its dynamic IP blocklist recently, as far as I can figure out. This has caused some problems.

Re: It may be coincidence...

From: azekeil
Date: February 21st, 2006 - 01:22 pm (Link)
Hm, that would do it :/

Re: It may be coincidence...

From: kingginger
Date: February 21st, 2006 - 01:04 pm (Link)
Yeah, that would be about right for what I am finding aswell.

Either mail is going off somewhere when being sent from them, or when mail is coming inbound the lookup is failing and can't find the domains.

Try as I might though I can't get hold of someone technical enough yet to be able to talk to and say "Hey, this is happening to quite a few people I know... Whats going on?".
From: mrz80
Date: February 21st, 2006 - 12:31 pm (Link)
I see that every so often, usually because of a kernel barf on our somewhat flaky IMAP server at Alachua Freenet. The folks what run UF's central IMAP and SMTP servers don't usually see much beyond "WHY's my email so [obscene gerund] SLOW??!?!!?" (The usual response is something like, "YOU try feeding 60,000 IMAP mailboxes and spamfiltring an entire University's worth of email on our hardware budget!" :-) ).

Once in a while I do see a bona fide "SMTP is broken for us!", but it's generally due to the group in question not registering their SMTP server with "the proper authorities" and hence we're not letting that server through our internet boundary ACLs. Technical problems "out there" with SMTP pretty much never come up for us that I've observed.

DNS spasms happen occasionally, but not all that often. DNS related problems usually boil to either a domain's expired, or a hostname's been typo'ed. :-)
From: babysimon
Date: February 21st, 2006 - 12:37 pm (Link)
Very rarely - the last time was when I made ry.com into a CNAME record. Didn't know that would kill the MX.
From: djm4
Date: February 21st, 2006 - 12:42 pm (Link)
We had a spate of them a year ago when some spam filters started getting sniffy about servers sitting at the end of ADSL connections. But otherwise they're rare.

almost never

From: bondagewoodelf
Date: February 21st, 2006 - 01:35 pm (Link)
I've only seen this where the target is an Exchange Server and people used Outlook internally to send it and they used an old distribution list entry from a previous mail that still contained the person that is now gone.