Carlos E. R. wrote:
On 21/09/2018 13.48, James Knott wrote:
On 09/21/2018 01:38 PM, Per Jessen wrote:
Google (gmail) I suspect does not allow talking on :25 without encryption, or the email can be easily read on transit. No, Google does not require TLS.
Actually, it does. I just tried setting my smtp server to port 25 & no security. I got this error message:
An error occurred while sending mail. The mail server responded: 5.7.0 Must issue a STARTTLS command first. i26-v6sm9327158ioj.33 - gsmtp. Please verify that your email address is correct in your account settings and try again.
So, it would appear STARTTLS is mandatory, so that encryption can be used. I also seem to recall Google saying SSL/TLS would be required to connect to their servers. They are heavily promoting encryption in general, even preferring https sites to http in web searches.
Yep :-)
Okay, let me post some output so you can both see: per@io64:~/Documents> dig gmail.com mx ; <<>> DiG 9.4.1-P1 <<>> gmail.com mx ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 43936 ;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 4, ADDITIONAL: 8 ;; QUESTION SECTION: ;gmail.com. IN MX ;; ANSWER SECTION: gmail.com. 3600 IN MX 5 gmail-smtp-in.l.google.com. gmail.com. 3600 IN MX 10 alt1.gmail-smtp-in.l.google.com. gmail.com. 3600 IN MX 20 alt2.gmail-smtp-in.l.google.com. gmail.com. 3600 IN MX 30 alt3.gmail-smtp-in.l.google.com. gmail.com. 3600 IN MX 40 alt4.gmail-smtp-in.l.google.com. per@io64:~/Documents> host gmail-smtp-in.l.google.com. gmail-smtp-in.l.google.com has address 173.194.79.27 gmail-smtp-in.l.google.com has IPv6 address 2a00:1450:4013:c05::1a per@io64:~/Documents> telnet 173.194.79.27 25 Trying 173.194.79.27... Connected to 173.194.79.27. Escape character is '^]'. 220 mx.google.com ESMTP x2-v6si4659966edq.366 - gsmtp EHLO klop99.example.com 250-mx.google.com at your service, [185.85.248.1] 250-SIZE 157286400 250-8BITMIME 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-PIPELINING 250-CHUNKING 250 SMTPUTF8 MAIL FROM: <per@jessen.ch> 250 2.1.0 OK x2-v6si4659966edq.366 - gsmtp RCPT TO: <pjessen55@gmail.com> 250 2.1.5 OK x2-v6si4659966edq.366 - gsmtp DATA 354 Go ahead x2-v6si4659966edq.366 - gsmtp From: per@jessen.ch To: pjessen55@gmail.com Subject: testing 6667 . 250 2.0.0 OK 1537551453 x2-v6si4659966edq.366 - gsmtp quit 221 2.0.0 closing connection x2-v6si4659966edq.366 - gsmtp Connection closed by foreign host. -- Per Jessen, Zürich (15.2°C) http://www.dns24.ch/ - your free DNS host, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org