Many "Proxmox SMTP server: errors from unknown..."

[cglmicro]

Since this morning, as an admin I'm receiving MANY emails with the subject "Proxmox SMTP server: errors from unknown[xxx.xxx.xxx.xxx]".
They all contains similar stuff :

Transcript of session follows.

 Out: 220 pmg10.legardeur.net ESMTP Proxmox
 In:  EHLO mta.email.jysk.ca
 Out: 250-pmg10.legardeur.net
 Out: 250-PIPELINING
 Out: 250-SIZE 41943040
 Out: 250-VRFY
 Out: 250-ETRN
 Out: 250-STARTTLS
 Out: 250-ENHANCEDSTATUSCODES
 Out: 250-8BITMIME
 Out: 250-SMTPUTF8
 Out: 250 CHUNKING
 In:  STARTTLS
 Out: 220 2.0.0 Ready to start TLS
 In:  EHLO mta.email.jysk.ca
 Out: 250-pmg10.legardeur.net
 Out: 250-PIPELINING
 Out: 250-SIZE 41943040
 Out: 250-VRFY
 Out: 250-ETRN
 Out: 250-ENHANCEDSTATUSCODES
 Out: 250-8BITMIME
 Out: 250-SMTPUTF8
 Out: 250 CHUNKING
 In:  MAIL
     FROM:<bounce-897_HTML-43555047-163454-526001905-13046@bounce.email.jysk.ca>
     BODY=8BITMIME
 Out: 250 2.1.0 Ok
 In:  RCPT TO:<myuser@mydomain.com>
 Out: 250 2.1.5 Ok
 In:  DATA
 Out: 354 End data with <CR><LF>.<CR><LF>
 Out: 451 4.3.0 Error: queue file write error
 In:  QUIT
 Out: 221 2.0.0 Bye


For other details, see the local mail logfile

On the few thousands legitimate emails hours that work fine, it look like these are SIMILARS ip's, and the keep trying to deliver every X minutes so I'v blackllisted them to stop the email flooding.:

161.71.69.123    foreo
161.71.38.86    hellofresh
    
13.110.209.11    snapfinancial
13.110.209.32    jysk
13.110.229.33    1800gotjunk
    
13.111.83.85    isagenix
13.111.110.27    lincoln
13.111.103.186    familiprix
13.111.34.95    itblues
13.111.56.47    sportexpert
13.111.52.28    keurig
13.111.204.1    westernunion
13.111.188.37    aloyoga
13.111.87.231    purolator
13.111.78.3    burton
    
136.147.138.153    netsol
136.147.185.21    pcoptimum
136.147.137.190    laura
    
209.85.208.43    baddesigngroup
    
198.245.88.33    macenzie

128.17.64.140    rogersbank
    
68.232.197.1    tuango

From what I see, the PTR of almost every IP address returns the same dns server *.exacttarget.com, and the PTR use always the same template starting with mta2.something.* like mta2.link.hellofresh.ca, or mta.e.rogersbank.com, or mta.mail.mackenzieinvestments.com.

Anyone else having issue with them today, or is it something broken in my cluster of 5 PMGs?

Thank you.

 

[Stoiko Ivanov]

Out: 451 4.3.0 Error: queue file write error

This might indicate that pmg-smtp-filter is not running - please check/share the journal of the node (+- 1hour of this mail)