One tip: for checking whether or not you have access to your vps @
host:port you ought to use netcat or telnet from your localhost:
https://www.digitalocean.com/community/tutorials/how-to-use-netcat-to-establish-and-test-tcp-and-udp-connections-on-a-vps
I frequently use telnet since you can also type in the protocol to a
server (assuming the server expects ascii) and get a response out of it.
E.g.
Type:
$ telnet xyzzy.com 80
Server response:
Trying 104.31.88.30...
Connected to xyzzy.com.
Escape character is '^]'.
Type:
GET / HTTP/1.0
Server response:
XYZZY
content="width=device-width,initial-scale=1,maximum-scale=1" />
You are in a twisty maze of passages, all alike.
[snip]
And yes in this case "curl" would be more a appropriate utility (for
http) but not for other protocols that curl doesn't support.
If you telnet to a port that isn't opened and being listened on:
$ telnet localhost 4321
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
telnet: connect to address 127.0.0.1: Connection refused
Trying fe80::1...
telnet: connect to address fe80::1: Connection refused
telnet: Unable to connect to remote host
Good day
Mike
On 8/17/18 18:05, Christy S wrote:
Hi all,
First a disclaimer. I have played with linux off and on for years, but
this is my first time trying to run a server completely on my own from
start to finish, well it's on a vps, but still. I'm pretty techie, but
a lot of this stuff is new to me, so I apologize for any *duh!*
questions. That said, I've so far installed dovecot, postfix,
wordpress, and related programs mostly successfully by following
tutorials. I say mostly successfully, because I'm having a really hard
time trying to get dovecot and postfix to behave together, and I'm
about at the end of what I know how to find on google.
If you're still with me and not groaning at yet another newbie asking
wtf did I do wrong questions, thank you! My basic setup is running
ubuntu 18 with up to date dovecot and postfix. Sasl is installed, and
I'm using a custom domain with all records successfully pointing to
the VPS.
As I mentioned, I've been following tutorials. My goal is to have a
mail server which can send and receive emails using this custom domain
both from the shell and, much more often, from my primary computer
using thunderbird. As there will likely only be two of us using this,
I'm completely fine with the setup using mailboxes that actually have
linux accounts. I'm also using maildir as the mailbox type.
Furthermore, I want to make sure to use ssl on any mail connections..
Normal passwords but ssl being used.
So, following one tutorial I set up postfix and dovecot, then went to
test it. The result was that while on the shell, I could send email to
my gmail account from the domain and receive it just fine. I could
also send mail from my gmail account to the domain and receive it on
the shel. I even managed to get imap to work, so I could receive
domain emails in thunderbird, after playing around with tb's settings.
However, if using tb I attempted to send an email using the custom
domain, smtp failed to connect.
I verified with my VPS provider that no, they do not block port 25,
465 or 587. I also verified that at, my home ISP, does not block
outgoing smtp traffic, considering I am using google's for my gmail
account. After hitting google again, I realized two things. One, for
some reason port 25 never got opened on UFW, so I fixed that. Second,
for some reason in all the stuff I did, postfix never got configured
to use SSL.
I found yet another tutorial, and ran through it to set up SSL with
postfix. However, in doing this I had to change a path for sasl, only
to find out later that doing that broke dovecot! Imap completely and
utterly stopped behaving.
Back to google again, and this time I found something a bit more up to
date which explained how to interconnect postfix and dovecot. It goes
through using mysql too, but I don't need that, so I skipped that
part. Changed the sasl path back to what it should be, told dovecot
and postfix to talk to each other and... Nope, still nothing.
I saw a warning that I should not use different certificates for
postfix and dovecot, so I told dovecot to look at the smtpd
certificate that I made. Not sure if that's what's breaking this or
something completely different, as I'm also brand new to the ssl
certificate creation process. So, here's the current status of using
thunderbird with my domain.
mail sent from gmail to new domain, never comes back in thunderbird
but doesn't bounce, either.
Mail sent via thunderbird to gmail from domain, works, but shows up as
from my gmail domain as well, which makes me think it's defaulting to
the gmail account even though the domain's smtp info is set up. This
could be because just before writing this message,
