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Dovecot, postfix pop3/imap server issue

Hi

I'm having a problem setting up Dovecot:

The command

Code:

#telnet user smtp

returns:
user/smtp: Temporary failure in name resolution.

Does this mean that there is a problem in the aliases file? (/etc/aliases)

Code:

#telnet localhost smtp

, works fine...

Here is the configuration!

postconf -n returns:

Code:

alias_database = hash:/etc/aliases

alias_maps = hash:/etc/aliases

broken_sasl_auth_clients = yes

command_directory = /usr/sbin

config_directory = /etc/postfix

daemon_directory = /usr/libexec/postfix

debug_peer_level = 2

home_mailbox = Maildir/

html_directory = no

inet_interfaces = all

mail_owner = postfix

mailq_path = /usr/bin/mailq.postfix

manpage_directory = /usr/share/man

mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain

mynetworks = 127.0.0.0/8

newaliases_path = /usr/bin/newaliases.postfix

queue_directory = /var/spool/postfix

readme_directory = /usr/share/doc/postfix-2.3.3/README_FILES

sample_directory = /usr/share/doc/postfix-2.3.3/samples

sendmail_path = /usr/sbin/sendmail.postfix

setgid_group = postdrop

smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination

smtpd_sasl_auth_enable = yes

smtpd_sasl_path = private/auth

smtpd_sasl_type = dovecot

unknown_local_recipient_reject_code = 550

Dovecot -n returns:

Code:

# 1.0.7: /etc/dovecot.conf

login_dir: /var/run/dovecot/login

login_executable(default): /usr/libexec/dovecot/imap-login

login_executable(imap): /usr/libexec/dovecot/imap-login

login_executable(pop3): /usr/libexec/dovecot/pop3-login

mail_location: maildir:~/Maildir/

mail_executable(default): /usr/libexec/dovecot/imap

mail_executable(imap): /usr/libexec/dovecot/imap

mail_executable(pop3): /usr/libexec/dovecot/pop3

mail_plugin_dir(default): /usr/lib64/dovecot/imap

mail_plugin_dir(imap): /usr/lib64/dovecot/imap

mail_plugin_dir(pop3): /usr/lib64/dovecot/pop3

imap_client_workarounds(default): delay-newmail outlook-idle netscape-eoh

imap_client_workarounds(imap): delay-newmail outlook-idle netscape-eoh

imap_client_workarounds(pop3): outlook-idle

pop3_client_workarounds(default):

pop3_client_workarounds(imap):

pop3_client_workarounds(pop3): outlook-no-nuls oe-ns-eoh

auth default:

  mechanisms: plain login

  passdb:

    driver: pam

  userdb:

    driver: passwd

  socket:

    type: listen

    client:

      path: /var/spool/postfix/private/auth

      mode: 432

      user: postfix

      group: postfix

aliases:

Code:

# Basic system aliases -- these MUST be present.

mailer-daemon:    postmaster

postmaster:    root



# General redirections for pseudo accounts.

bin:        root

daemon:        root

adm:        root

lp:        root

sync:        root

shutdown:    root

halt:        root

mail:        root

news:        root

uucp:        root

operator:    root

games:        root

gopher:        root

ftp:        root

nobody:        root

radiusd:    root

nut:        root

dbus:        root

vcsa:        root

canna:        root

wnn:        root

rpm:        root

nscd:        root

pcap:        root

apache:        root

webalizer:    root

dovecot:    root

fax:        root

quagga:        root

radvd:        root

pvm:        root

amanda:        root

privoxy:    root

ident:        root

named:        root

xfs:        root

gdm:        root

mailnull:    root

postgres:    root

sshd:        root

smmsp:        root

postfix:    root

netdump:    root

ldap:        root

squid:        root

ntp:        root

mysql:        root

desktop:    root

rpcuser:    root

rpc:        root

nfsnobody:    root



ingres:        root

system:        root

toor:        root

manager:    root

dumper:        root

abuse:        root



newsadm:    news

newsadmin:    news

usenet:        news

ftpadm:        ftp

ftpadmin:    ftp

ftp-adm:    ftp

ftp-admin:    ftp

www:        webmaster

webmaster:    root

noc:        root

security:    root

hostmaster:    root

info:        postmaster

marketing:    postmaster

sales:        postmaster

support:    postmaster





# trap decode to catch security attacks

decode:        root



# Person who should get root's mail

#root:        marc

Please be gentle with responses, I'm a newbie regarding Linux and mail servers =)

//Konduktorn

The telnet command is;

Code:

telnet <hostname> <port>

Unless you have a host (machine) on your network that you refer to as "user" then the connection wont work. However, that's why your second entry does work.

Code:

telnet localhost smtp

Localhost is a shorthand way of refering the local machine (it translates to an IP address of 127.0.0.1)

You can set up shorthand names for machines by editing the file /etc/hosts Although be sure to back it up as it's kind of important.

The smtp part is also short hand. It looks up a port number from a list of known ports/services (I think from /etc/services). So you could in fact re-write the whole command as;

Code:

telnet 127.0.0.1 25

And have the same effect.

In short, the machine name "user" doesn't mean anything to the machine you're on. hence the error of failure in name resolution.

As a side point; are you actually using Dovecot as an SMTP server? It normally acts as an IMAP server which you'll find on port 143.

Try the following two commands and see what service responds to you.

Code:

telnet localhost smtp

Code:

telnet localhost imap

Enjoy

Quote:

Originally Posted by redgoblin (Post 3868254)

The telnet command is;

Code:

telnet <hostname> <port>

Unless you have a host (machine) on your network that you refer to as "user" then the connection wont work. However, that's why your second entry does work.

Code:

telnet localhost smtp

Code:

telnet 127.0.0.1 25

Code:

telnet localhost smtp

Code:

telnet localhost imap

Enjoy

Thank you very much for clearing up!

Perhaps you'll be able to assist me further:

I registered a domain at dyndns.com, example.mine.nu
How do i "Bind" this to my server, to the mail addresses so to speak, if you understand?

And also, how do I register this on MX records?

I hope you understand what I mean, I'm used to all the names and terms.

/Konduktorn

I haven't used dyndns so this might be a bit vague. If anyone else has they might be able to offer better advice.

You need to tell dyndns what your IP address is. If you're on a connection that changes IP periodically then you'll need a way to update your dyndns record. That's a separate problem and probably best to try they're help files or forums.

Once you've entered your IP address into your account all requests to your domain (example.mine.nu) will be sent to your modem/router.

If you're using a router than you need to set up some kind of port forwarding from the router to the machine that runs the service you're trying to serve. Obviously forward the required port. 25 for mail, 22 for ssh, 80 for web. If you have access to an account on an outside machine you can now test that with your new found telnet skills ;) By using telnet (from the outside) you should get a connection to the appropriate service.

MX records are simple a subset of a DNS record used specifically by email. It means that you can host your email on a separate machine to your webserver. In your case you simple want your MX record to point to the same IP as the rest of your domain.

In summary what you want is;

1) Correct IP address in dyndns
2) Same IP for your MX record
3) Set up port forwarding on your router to pass the connection to the correct machine.
4) Set up a service on the receiving machine.

Sorry that's not more specific. You best bet from here is to google around for a few examples on seting up web/mail servers on your distribution.

One thing to always keep in mind. If you open up a service to the outside world it's very important that you keep that machine up to date and consider any possible insecure setups. It's a hostile world out there on the net.

Good luck, don't give up and remember google/man pages are your friend.