Non-user logins?

[Stephen Hanselman]

Ken,
Both of my production servers see the exact same problem.  What was worse I was seeing around 100K failed attempts to login to my root user. A bit of research and now my firewall ignores any attempt from PRC.

Sort of a cost of doing business 

Steve Hanselman

Sent from my iPad

> On Jan 7, 2022, at 20:24, Ken Wright <daddywarlock at gmail.com> wrote:
> 
> My Dovecot issues continue.  Right now I see at least two issues: 
> first, my logs consistently show non-users trying (and failing) to log
> in, and I'm still unable to log in from my email client (Evolution or
> Roundcube, either one).
> 
> I'll post about the second issue later; right now I wonder why I'm
> getting so many non-users trying to log in.  Am I the subject of 
> concerted hacking attacks, or is there something else going on?  Some
> of the attempted logins are more-or-less random names claiming to be
> @mydomain, but at least one is a username that's really on my server,
> to wit:
> 
> Jan  7 22:52:01 grace dovecot: lmtp(776281): Error: lmtp-server: conn
> unix:pid=776262,uid=117 [3]: rcpt www-data at mydomain.com: Failed to
> lookup user www-data at mydomain.com: Internal error occurred. Refer to
> server log for more information.
> 
> (Another quick question:  which server log should I check?)
> 
> So, if anyone can tell me what's going on with all these logins, I'd be
> much obliged!
> 
> 
> Ken
>