For the past couple of days, I have been getting the following errors when trying to relay mail via mail.synchro.net.
0036 SEND/TLS [mail.synchro.net] WARNING 'Bad/unrecognized data format' (-32) setting session active
1/31 11:02:38 mail 0036 SEND connecting to port 587 on mail.synchro.net [71.95.196.36]
1/31 11:02:38 mail 0036 SEND !INVALID RESPONSE: '421 System Error: Maximum connections exceeded, try again later' Expected: '220'
1/31 11:02:38 mail 0036 SEND mail.synchro.net replied with: "421 System Error: Maximum connections exceeded, try again later" instead of the expected reply: "220 ..."
The system tries again later and gets the same response. Could there be a boo-boo on my end that is causing that response, or is it something going on at the server end?
The system tries again later and gets the same response. Could there be a boo-boo on my end that is causing that response, or is it something going o
at the server end?
I was probably just under a botnet attack at that time. I have my SMTP[S] serv
set to 100 clients, which is normally plenty, but the botnets can time connec
thousands of a clients at a time (or try to), thus starving out legit clients.
ust try again, it looks fine right now.
The system tries again later and gets the same response. Could there be a boo-boo on my end that is causing that response, or is it something going o
at the server end?
I was probably just under a botnet attack at that time. I have my SMTP[S] serv
set to 100 clients, which is normally plenty, but the botnets can time connec
thousands of a clients at a time (or try to), thus starving out legit clients.
ust try again, it looks fine right now.
Thanks. I have had some issues with them lately also, but not to near that volume. I will watch it and see if the mail is still stuck.
Nope. Mail is still stuck.
Nope. Mail is still stuck.
Can you elaborate?
mail.synchro.net seems to be accepting incoming connections just fine right now: $ nc mail.synchro.net 25
Re: Re: email relay error
By: Digital Man to Dumas Walker on Thu Feb 01 2024 11:48 am
Nope. Mail is still stuck.
Can you elaborate?
mail.synchro.net seems to be accepting incoming connections just fine right now: $ nc mail.synchro.net 25
ive been getting errors too, just recieved "error 421, maximum connections exceeded, try later" when connection to you server. its been trying with an email I sent earlier this morning.
What IP address are you connecting from?
Nope. Mail is still stuck.
Can you elaborate?
mail.synchro.net seems to be accepting incoming connections just fine right no
$ nc mail.synchro.net 25
220 cvs.synchro.net Synchronet SMTP Server 3.20a-Linux Ready
Re: Re: email relay error
By: Digital Man to kk4qbn on Thu Feb 01 2024 11:55 pm
What IP address are you connecting from?
174.80.5.232
My IPA is 67.131.57.133. Thanks!
Are you running multiple instances of SBBS or some other mail server that's trying to send at the same time as Synchronet sendmail thread? The Synchronet sendmail thread is a single thread that seconds a single email at a time over a single TCP connection, so it seems there's something going on here weird from your end maybe.
What IP address are you connecting from?
174.80.5.232
Looks like my mail server is getting multiple concurrent connections from that IP without a successful authentication:
2024-02-01T18:52:50.703533-08:00 git sbbs: mail 0860 SMTPS [174.80.5.232] ERROR 'Received TLS alert message: Handshake failure' (-15) setting session active 2024-02-01T18:52:50.703598-08:00 git sbbs: mail 0860 SMTP [174.80.5.232] Session thread terminated (3 threads remain, 8710 clients served)
Are you running multiple instances of SBBS or some other mail server
Are you running multiple instances of SBBS or some other mail server that's
trying to send at the same time as Synchronet sendmail thread? The
Synchronet sendmail thread is a single thread that seconds a single email
Since there's at least one other sysop with the same/similar issue, I think it's a regression in the SMTPS support, probably on the sendmail thread side. I'm conferring with Deuce about it.
Thanks. Looks to be a recent regression with SMTPS support either on the sendi
(Synchronet sendmail thread) side or the SMTP server side. I assume you've up
ted from git fairly recently?
vert.synchro.net reporting delivery failure of message after 51 attempts
from Mike Powell to CCOKY@ILGOU.COM
Reason:
ERROR 10061 connecting to SMTP server: ILGOU.COM
Digital Man wrote to Dumas Walker <=-
I was probably just under a botnet attack at that time. I have my
SMTP[S] server set to 100 clients, which is normally plenty, but the botnets can time connect thousands of a clients at a time (or try to), thus starving out legit clients. Just try again, it looks fine right
now. --
No actually I have not. I am still running 3.19.
I thought they al gave up and opened outlook.com addresses - at least
all of the spams I see look to come from Microsoft...
Re: Re: email relay error
By: Dumas Walker to DIGITAL MAN on Sat Feb 03 2024 10:13 am
No actually I have not. I am still running 3.19.
Okay, thanks, that's good to know.
I've increased the max concurrent connections to 2 at mail.synchro.net, so that should resolve the issue. --
Re: Re: email relay error
By: Dumas Walker to DIGITAL MAN on Sat Feb 03 2024 10:13 am
No actually I have not. I am still running 3.19.
Okay, thanks, that's good to know.
I've increased the max concurrent connections to 2 at mail.synchro.net, so tha
should resolve the issue.
I thought they al gave up and opened outlook.com addresses - at least
all of the spams I see look to come from Microsoft...
I've increased the max concurrent connections to 2 at mail.synchro.net, so that should resolve the issue. --
thaRe: Re: email relay error
By: Dumas Walker to DIGITAL MAN on Sat Feb 03 2024 10:13 am
No actually I have not. I am still running 3.19.
Okay, thanks, that's good to know.
I've increased the max concurrent connections to 2 at mail.synchro.net, so
should resolve the issue.