[BlueOnyx:26688] Updating users password results inability to access inbox on local network

[Chad A. Bersche]

I've got a bit of a stumper on an account password change.

I updated a local userid to have a new password.  I also updated the 
user's password on their iPhone.  The phone is often on the same LAN as 
the mail server.  I have DNS entries that sort out the IP address of the 
mail hostname when on the local network, and when on a mobile network, 
the external DNS entries point to the valid external accessible IP to 
the same host.  Now comes the weird part: When on the local network, my 
iPhone gives a "Cannot get Mail  No password provided for 
"maskedemail at maskeddomain.com".  However when I switch to the LTE 
network and attempt to fetch mail, all goes according to plan. I've 
pulled some of the maillog entries from the logins:


Logging in from local network:

Dec 27 22:19:12 mail dovecot[3058731]: imap-login: Disconnected: Aborted 
login by logging out (auth failed, 2 attempts in 8 secs): user=<masked>, 
method=PLAIN, rip=172.18.0.35, lip=172.18.170.213, TLS, 
session=<2jRFN4oNqNesEgAj>
Dec 27 22:19:24 mail dovecot[3058731]: imap-login: Disconnected: Aborted 
login by logging out (auth failed, 2 attempts in 12 secs): 
user=<masked>, method=PLAIN, rip=172.18.0.35, lip=172.18.170.213, TLS, 
session=<E9nBN4oNqdesEgAj>


Logging in from Mobile/LTE network:
Dec 27 22:20:03 mail dovecot[3058731]: imap-login: Login: user=<masked>, 
method=PLAIN, rip=174.243.50.183, lip=172.18.170.213, mpid=3928153, TLS, 
session=<BwfGOooNESuu8zK3>
Dec 27 22:20:03 mail dovecot[3058731]: imap-login: Login: user=<masked>, 
method=PLAIN, rip=174.243.50.183, lip=172.18.170.213, mpid=3928154, TLS, 
session=<PrrGOooNACuu8zK3>


As you can tell from the timestamps, these are just a minute apart, and 
NO change of password, etc. was involved.  Simply changing from the 
local network to LTE causes the problem.  This worked flawlessly prior 
to the password update, and I'm scratching my head as to why this is 
problematic.  I'm thinking it's got something to do with certificates, 
but again, all this worked before, and none of my certificates have 
changed; only the password changed.

Any insight as to why this behavior would be shown now, and any thoughts 
about remedy?


Thanks!

   -- Chad