[TriLUG] semi-OT: mail relaying broken for other time warner customers?

[Lisa Lorenzin via TriLUG]

hi all,

[this is semi-OT because it isn't a linux issue, it's an internet-provider 
issue, but hopefully not totally OT, because our home mail setup is 
sendmail on linux!)

is anyone else using time warner for outbound email relaying from a home 
mailserver?  if so, did they break your outbound email relaying - with no 
warning - last
monday, too?

it looks like they have a) turned on a requirement for authentication on 
smtp-server.nc.rr.com and b) are furthermore only allowing relaying for 
messages where the
>From address matches the account used to authenticate. which totally 
breaks our home email setup for outbound email.  this change seems 
correlated to our cable modem
IP address changing from 71.x.x.x to 45.x.x.x.x.

1000plus.com mail is running on a linux server in our basement - we have 
residential cable model service with time warner.  time warner gives a 
dynamic public IP
address to our cable modem, and we're using dyndns.org to keep our 
1000plus.com DNS updated to that address.  sendmail is configured to relay 
outbound mail through
smtp-server.nc.rr.com

this rube-goldberg setup has been working well for the past _ten years_. 
last monday, 3/16, i sent an outbound email and a couple hours later 
received a bounce
message:

  ----- The following addresses had permanent fatal errors -----
<mbroome at employees.org>
     (reason: 530 Authentication is required before sending [R0107005])

    ----- Transcript of session follows -----
... while talking to smtp-server.nc.rr.com:
> > > MAIL From:<mike at 1000plus.com>
<<< 530 Authentication is required before sending [R0107005]
554 5.0.0 Service unavailable

mike dug around in the bowels of the time warner website and found some 
information about needing to authenticate with my nc.rr.com account, which 
i had literally
never used before. we managed to set a password and configured sendmail 
for SMTP auth, at which point the bounce message changed to:

  ----- The following addresses had permanent fatal errors -----
<mbroome at employees.org>
     (reason: 554 From address must match authentication [R0107004])

    ----- Transcript of session follows -----
... while talking to smtp-server.nc.rr.com:
> > > MAIL From:<mike at 1000plus.com> AUTH=<>
<<< 554 From address must match authentication [R0107004]
554 5.0.0 Service unavailable

these problems appear to be correlated with a change in cable modem IP 
address from the 71.x.x.x subnet to the 45.x.x.x subnet

before these problems started, we had a 71.x.x.x IP address. time warner's 
network has been sucking donkey balls lately (DNS servers unreachable, 
20-_second_ tracert
hops between internal routers) so we rebooted our cable modem at some 
point while trying to figure out what the hell was going on with that, and 
we got a 45.x.x.x IP
address instead.  the mail bounces started showing up after we got the 
45.x.x.x address.

we had another round of cable modem reboots midweek and briefly got a 
71.x.x.x address again, at which point outbound email worked again, but 
had to reboot again and
landed back in the slums of 45.x.x.x with the same problem.

anyway, just curious whether anyone else has run into this issue and, if 
so, what you did to get TWC to resolve it.  after two hours on the phone 
with TWC support,
two conversations with tier III TAC, and two attempts to escalate to the 
NOC, we do not appear to be any closer to having working outbound email 
relay than we were
last monday. :(

                                         regards,

                                                 lisa

-- 
lisa lorenzin
lisa at trilug.org