Error messages in Dovecot and Mail log

NethServer Version: 7.6
Module: Dovecot

I don’t seem to be able to send mail from Thunderbird anymore. I checked the SMTP settings in TBird, but they are ok.
I also don’t receive mail from external mailadresses. I do receive server mails (like fail2ban) that I configured to send to my mailbox.

I am getting quite some messages in Dovecot log similar to this:
dovecot: imap(rob@domain.tld): Error: mmap(size=3965655700) failed with file /var/lib/nethserver/vmail/rob@domain.tld/Maildir/dovecot.index.cache: Cannot allocate memory

In mail.log I see this when trying to send an email from thunderbird:

Mar 15 12:03:54 ns7 postfix/qmgr[5652]: 423E7800145: from=<rob@domain.tld>, size=3957, nrcpt=1 (queue active) Mar 15 12:03:55 ns7 postfix/smtp[24436]: Untrusted TLS connection established to mx01.emig.gmx.net[212.227.17.5]:25: TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits) Mar 15 12:03:55 ns7 postfix/smtp[24436]: 423E7800145: host mx01.emig.gmx.net[212.227.17.5] said: 451 Requested action aborted: local error in processing (in reply to MAIL FROM command) Mar 15 12:03:55 ns7 postfix/smtp[24436]: Untrusted TLS connection established to mx00.emig.gmx.net[212.227.15.9]:25: TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits) Mar 15 12:03:55 ns7 postfix/smtp[24436]: 423E7800145: to=<username@gmx.net>, relay=mx00.emig.gmx.net[212.227.15.9]:25, delay=400, delays=399/0.02/0.41/0.65, dsn=4.0.0, status=deferred (host mx00.emig.gmx.net[212.227.15.9] said: 451 Requested action aborted: local error in processing (in reply to MAIL FROM command))

It looks like some memory allocation problem. However the total amount of available memory is more than sufficient. Also the total mailbox size is not that horrific (400MB) that it should not work. The max mailbox size on the server is set to 15GB.

Any troubleshooting help is appreciated…

Sorry for point out a bit more this section:
Which version of TB are you using?
How’s configure TB for deliver to SMTP?
Have you already tried to deliver mail from WebMAIL?
Are you using Windows or Linux Client?
If the first one, do your antivirus filter SMTP ports for check?

The cache file may be corrupted.
You can delete it, better if you keep tbird closed while doing it.
It will be recreated when you access the mbox again.

@filippo_carletti I see the cache file has been recreated. But now I get the message in TBird that it can’t connect to the mailserver.
I can open the SOGo webpage, and when sending a mail it confirms it has been sent successfully, but the mail does not get delivered.

@pike: since the same problems occur when using webmail, I don’t think it is a Tbird issue, but more a Dovecot or Postfix issue…

/edit: looks like it is an upstream DNS problem. I just looked at the DNS records for my domain and I see a message from the domain reseller:

DNS failure
There is currently a failure with nszero DNS servers. Because of this, the records cannot be resolved or managed, we are of course working urgently to resolve this.

Let’s sit this failure out and have a look again when they solved this… :-/

/edit: it was the DNS failure from the domain provider… I realy need to think over if I want to stay there… it took them over 12 hours to get things fixed…
I only had a handful domains, but I heard on their forums that there were people having over 1000 domains with DNS records of multiple subdomains per domain that were not reachable whole day…
I had to add my mailserver in /etc/hosts to be able to mail from TBird… :-1: