panic: dial tcp 127.0.0.1:2525: getsockopt: connection refused

[slowkow]

Expected behavior

In the multipass login form, when I click submit, I expect to receive an email to the address I entered.

Observed behavior

caddy crashes with this error when I click submit:

caddy -conf=/etc/caddy/Caddyfile -log stdout
Activating privacy features... done.
multipass for https://test.quickgene.net is initialized
https://test.quickgene.net
2017/01/19 13:01:11 https://test.quickgene.net
http://test.quickgene.net
2017/01/19 13:01:11 http://test.quickgene.net
WARNING: File descriptor limit 1024 is too low for production servers. At least 8192 is recommended. Fix with "ulimit -n 8192".
panic: dial tcp 127.0.0.1:2525: getsockopt: connection refused

goroutine 21 [running]:
panic(0xbb0c20, 0xc4201dcbe0)
        /usr/local/go/src/runtime/panic.go:500 +0x1a1
github.com/namsral/multipass/services/email.NewUserService.func1(0xc4203ac120, 0xc42019fd50)
        /home/caddy/go/src/github.com/namsral/multipass/services/email/email.go:125 +0x27f
created by github.com/namsral/multipass/services/email.NewUserService
        /home/caddy/go/src/github.com/namsral/multipass/services/email/email.go:141 +0x495

Caddyfile:

test.mydomain.net {
  root /var/www/test.mydomain.net
  multipass {
    resources /
    smtp_addr 127.0.0.1:2525
    handles myusername@gmail.com
    mail_from "Multipass <no-reply@mydomain.net>"
  }
}

[namsral]

Reading the trace, it seems there isn't any SMTP server available on host 127.0.0.1 with port 2525.

panic: dial tcp 127.0.0.1:2525: getsockopt: connection refused

A nasty panic none the less.

[slowkow]

Could I please ask you to recommend the next steps to get this working? For example, how did you get this working on your own sites?

[namsral]

Since you mentioned Gmail in your examples, the following example uses a gmail account:

multipass {
    resources /authenticaed
    handles myusername@gmail.com
    mail_from "Multipass <myusername@gmail.com>"
    smtp_server smtp.gmail.com:465
    smtp_user   myusername@gmail.com
    smtp_pass   secret
}

Just replace the myusername and secret credentials with your own.

[slowkow]

Thank you! I appreciate the help. Now I'm starting to remember how the SMTP server is supposed to work again.

I tried the settings you suggested, and this is the error I get now. Do you have any tips to get past this error?

Thanks to your comment, I remember now that I also setup Amazon SES and Mailgun SMTP servers, so I went ahead and tried my Mailgun server and credentials instead of Gmail. However, it gives the same error.

caddy -conf=/etc/caddy/Caddyfile -log stdout
Activating privacy features... done.
multipass for https://test.mydomain.net is initialized
https://test.mydomain.net
2017/01/19 18:25:45 https://test.mydomain.net
http://test.mydomain.net
2017/01/19 18:25:45 http://test.mydomain.net
WARNING: File descriptor limit 1024 is too low for production servers. At least 8192 is recommended. Fix with "ulimit -n 8192".
panic: x509: certificate is valid for ip-123-45-6-789, not localhost

goroutine 21 [running]:
panic(0xbdf3a0, 0xc42006bb80)
        /usr/local/go/src/runtime/panic.go:500 +0x1a1
github.com/namsral/multipass/services/email.NewUserService.func1(0xc420374120, 0xc420193d50)
        /home/caddy/go/src/github.com/namsral/multipass/services/email/email.go:125 +0x27f
created by github.com/namsral/multipass/services/email.NewUserService
        /home/caddy/go/src/github.com/namsral/multipass/services/email/email.go:141 +0x495

[namsral]

panic: x509: certificate is valid for ip-123-45-6-789, not localhost

There is a mismatch in the hostname of the SSL/TLS certificate used for the SMTP connection. And the IP referenced in the error is non-existant, 123.45.6.789? Something is off in your setup.

[slowkow]

Indeed, I manually censored the IP address in the pasted code snippet.

Yes, the conflict is about the mismatch. Unfortunately, I can't seem to find any hints about how to resolve this. I was hoping that maybe you might have run into this same error on your servers. Any hints would be greatly appreciated. I'm learning as I go.

For example, is there some way to manually inspect the certificate? Where is it located? Can I modify it? Why don't I run into this type of issue with Apache and only trigger the error with Caddy?

Related issues

This error seems to be related, there are no instructions for resolution:

• http://stackoverflow.com/questions/25979835/x509-certificate-issue-with-go-smtp-sendmail

The gomail package describes this error in the README, but there is no resolution there either:

• https://github.com/go-gomail/gomail#x509-certificate-signed-by-unknown-authority

If you get this error it means the certificate used by the SMTP server is not considered valid by the client running Gomail.

CheckTLS

I ran the TLS Sender Test from my server by sending an email to test@TestSender.CheckTLS.com with this script and it worked:

email_to="test@TestSender.CheckTLS.com"
email_subject="a8jqbpup4xtbt"
email_text="This is a test message."

curl -s --user 'api:MY_API_KEY' \
 https://api.mailgun.net/v3/MY_DOMAIN/messages \
 -F o:require-tls='true' \
 -F o:skip-verification='false' \
 -F from='K S <MY_USERNAME@gmail.com>' \
 -F to="$email_to" \
 -F subject="$email_subject" \
 -F text="$email_text"

I got the reply:

Your email was successfully sent securely using TLS.

A transcript of the eMail SMTP session is below:
[REDACTED]

[namsral]

For example, is there some way to manually inspect the certificate?

Use the openssl cli and connect to the receiving side to inspect the certificate.

Connect the client (gomail) to a SMTP server you control and log the TLS handshake.

The gomail package describes this error in the README

That's a different error regarding self-signed certificates.

What's configured for smtp_addr in your multipass directive?

[namsral]

I use a SMTP client like nullmailer to send emails.

multipass {
    smtp_client /usr/sbin/sendmail -t -i
    mail_from "Multipass <no-reply@dallas>"
    ...

This has the advantaged of having the SMTP client handling all the nasties; message queue, fails, retries, etc.

Support for SMTP clients was added in 99ad323, see #11.

[slowkow]

I still get the same error:

panic: x509: certificate is valid for ip-172-30-1-238, not localhost

I tried smtp_client as you suggested, and GMail, and Mailgun. All of them give me the same error.

Here is my Caddyfile:

test.mydomain.net {
  root /var/www/test.mydomain.net
  multipass {
    resources /
    handles myusername@gmail.com

    smtp_client  /usr/sbin/sendmail -t -i
    mail_from   "Multipass <no-reply@mydomain.net>"

    #smtp_server smtp.mailgun.org:587
    #smtp_user   postmaster@mg.mydomain.net
    #smtp_pass   MAILGUN_PASSWORD

    #smtp_server smtp.gmail.com:465
    #smtp_user   myusername@gmail.com
    #smtp_pass   GMAIL_PASSWORD
  }
}

Notably, I can successfully send myself an email from the server with:

echo "this is a test" | mail -s "testing $(date)" myusername@gmail.com

Thanks for your patience with me on this issue! I appreciate it.

[namsral]

I still get the same error:

Please provide the whole trace.

Are you using a Multipass binary from the releases page?