Ubuntu/postfix
 

i have been put in charge of installing a new SMTP server. so, i have decided to broaden myself and get into linux... here is what i have and here is the problem. i have ubuntu server installed (honestly i'm not too sure which flavor...i want to say gutsy gibbon). also, ubuntu has been installed as a virtual machine using VMWARE 1.5. to help a hack like me, i installed webmin because i am not too comfortable at the command line. next i installed and started postfix. went great. just for the fun of it, i sent some mail from the webmin/postfix console using one of the built-in user mailboxes...mail delivered perfectly. here is my problem. when i try to send mail from a simple mail client, the client connects to the server, but times out trying to send. i have tried to disable all autentication...this server is on my LAN behind firewalls, so i have no need for authentication to send mail. also, i have checked the boxes to accept all smtp mail clients and disabled all encryption. any ideas? thanks - shagcarpet

From the client machine, can you telnet to port 25 on the server? Do you have a firewall blocking port 25? What is the output of "postconf -n"?

thanks for the reply. i can see that what you say is probably the issue. when i telnet to the linux box, "telnet 10.19.6.47 25", it appears to connect, but comes back with a black screen with the cursosr flashing... when i type, the cursor moves but no characters are displayed. when i hit enter the cursor jumps to the next line. have i hosed the config? here is the optput of "postconf -n", run from the command shell in webmin.

> postconf -n
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
append_dot_mydomain = no
biff = no
broken_sasl_auth_clients = yes
config_directory = /etc/postfix
inet_interfaces = all
inet_protocols = all
mailbox_command = procmail -a "$EXTENSION"
mailbox_size_limit = 0
mydestination = eca-ubuntu.******.net, localhost.******.net, , localhost
myhostname = eca-ubuntu.*******.net
mynetworks = 10.19.6.0/24
myorigin = /etc/mailname
recipient_delimiter = +
relayhost =
smtp_tls_session_cache_database = btree:${queue_directory}/smtp_scache
smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
smtpd_delay_reject = no
smtpd_recipient_restrictions = permit_mynetworks permit_inet_interfaces permit_sasl_authenticated permit_mx_backup
smtpd_sasl_security_options =
smtpd_tls_session_cache_database = btree:${queue_directory}/smtpd_scache

Any takers on this one? I have worn Google out looking for an answer... Thanks...

Let's confirm two things:

a) you can/cannot connect from localhost
b) you can/cannot connect from another host

For (a), on the postfix host itself, type:

telnet localhost 25

and report the output here.

For (b), on a different host (even a windows host would be fine), perform

telnet ip.addr.of.postfix-server 25

and report the output here.

Thanks for the reply...
both (a) and (b) have the same results.
i assume i connect each way, i see just a black screen with the cursor flashing...if I type anything, the cursor moves but nothing is displayed. when i hit enter it jumps to the next line.
also...when i try to send mail thru it (using windows mail), the client says connected for about a minute, then comes back with a timeout error.

Sounds like iptables is blocking the connection. Run and show output from:

iptables -L
netstat -an --tcp | grep 25

thanks again for the quick reply...

> iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination


> netstat -an --tcp | grep 25
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN
tcp 1 0 10.19.6.47:25 10.19.6.28:2773 CLOSE_WAIT
tcp6 0 0 :::25 :::* LISTEN

Something is not right. You should at least be getting something like:

$ telnet localhost 25
Connecting to localhost...


from the test where you tried connecting from the postfix server machine itself. Are you running the localhost test on the native host or the guest OS?

yeah...something definitely doesn't seem right. i have limited experience with linux, but many years of windows/server experience...i've never seen a telnet session do stuff like this.

i ran the localhost test on the guest OS (which is Ubuntu)...native host is Windows 2003. test from another host was run from another windows 2003 server on same LAN segment. again, both have the same results. is a reload in order?

ok...i lied...
from the local host, i do get-
trying 127.0.0.1...
connected to localhost....
escape character is '^]'.

but i never get the 220 message.
it really won't take any commands at this point except ctrl-alt-del to reboot...

If there is no listening service, you will get an immediate Connection refused message. Example:
If a service is listening and accepts the connection, you will get a Connected to host message:

You are getting the connection message, so the connection has been accepted by the listening service.

What shows up in your maillog when you run the telnet test ?

Let the connection sit for about 1 minute - see what happens both on screen and in the log.

You don't need to reboot to exit telnet. The message "Escape character is '^]' means you can hit Control-Escape to force telnet to give you back command control. Then you can just type quit.