Port 25 blocked since updates

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rtroha48
Posts: 1
Joined: 2010/05/17 21:21:01

Port 25 blocked since updates

Post by rtroha48 » 2010/05/17 21:46:10

Last night I installed all the updates that were available for CentOS. Today, I discovered that all connections to port 25 (Sendmail) are being blocked except connections coming from localhost.

I tried disabling the firewall to see if anything would change but it is still blocked.

If it is not the firewall doing the blocking, what else might it be?

chuina
Posts: 355
Joined: 2009/12/11 10:25:56

Re: Port 25 blocked since updates

Post by chuina » 2010/05/18 01:33:27

Welcome to the CentOS

Required readings for all new members are [url=http://www.centos.org/modules/newbb/viewforum.php?forum=47]FAQ & Readme First[/url].

Did you use any third party tool for configuring firewall before update ?

Just to make sure, as root, what is the output of
[code]netstat -tulpn | grep sendmail[/code]

abednegoyulo
Posts: 550
Joined: 2007/12/26 06:24:38
Location: 127.0.0.2 44013

Re: Port 25 blocked since updates

Post by abednegoyulo » 2010/05/18 01:35:21

Sounds like it is only listening on 127.0.0.1. I have no experience in sendmail but this [url=http://lists.samba.org/archive/linux/2002-August/004310.html]link[/url] might help.

hi_vkkadam
Posts: 74
Joined: 2007/11/05 16:08:34
Location: Pune

Port 25 blocked since updates

Post by hi_vkkadam » 2010/05/19 10:12:16

Hi,

first flush all firewall rules
iptables -F
say 'lokkit' and disable the filewall
service iptables stop

now open the /etc/mail/sendmail.mc file and
comment the as

dnl # DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl

it will listen on all interfaces or you can specify the ip address to listen on

then say mc sendmai.mc>sendmail.cf

then service sendmail restart

Thanks
Vijay kadam

chuina
Posts: 355
Joined: 2009/12/11 10:25:56

Re: Port 25 blocked since updates

Post by chuina » 2010/05/19 20:44:54

[quote]rtroha48 wrote:
Last night I installed all the updates that were available for CentOS. Today, I discovered that all connections to port 25 (Sendmail) are being blocked except connections coming from localhost.[/quote]
The question is : Does the update change sendmail configuration file ?

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