Server :: Block Email Sending And Receiving Using Squid
Jun 17, 2010
i am using centos 5.4, running squid for proxy, i want to block email sending and receiving of proxy users to secure my data. how is it possible that the proxy user can only brows websites but he can not receive or open and send or save as draft to mail box.
I have a small internal network with about 8 or so servers or workstations. My mail server is getting spammed from all over to the root and other administrative accounts. I also get valid email sent to the root and administrative accounts from within my local network. Is there a way to block all email coming from outside my local network while still receiving it inside the local network to these specific accounts?
i have a problem regarding our email server. all the users can send email but they cant received mail. .when hitting send receive on outlook there were no error found. .i have already reboot the server and restarted the sendmail services but still same problem.
Yesterday i run a postfix everything works fine and today it hangs up. if i dial "telnet localhost 25" i get (before day i get 220 answer and ordinary hello):
Code: Trying 62.197.207.43... Connected to trons.sk. Escape character is '^]'. and nothing go far.
I have followed the guide for "The Perfect Server - Debian Lenny (Debian 5.0) With BIND & Dovecot [ISPConfig 3]" and all is well, except.
I can send mail (to GMail) from commandline. I can send mail (to GMail) from any of the domains configured in ISPConfig3 through SquirrelMail (how ever terrible that looks, but functions) or IMAP/POP.
but....
I can't receive mail (from GMail) on any of the domains configured in ISPConfig3 in SquirrelMail or IMAP/POP.
I have my domains configured with proper MX records (just like I have them configured at work). I have all ports (80, 143, 110, 25, 22, etc) forwarded on my router that are needed.
I can Telnet to localhost and all checks are fine. I can send and receive from and to local domains on the same server, which makes sense. but
I can't Telnet from any external server to my server behind NAT.
Conclusion:
I figured it MUST be a network/port-forwarding problem as the external Telnet requests fails to my machine on port 25.
Tested my router if it would let met communicate through port 25 and it would.
So it must be my ISP, as I read in different posts.
Question:
Maybe I'm a n00b, but in all other posts the problems were with receiving AND sending.
My ISP responded that port 25 is blocked because of spam issues.
But I can mail (and even spam if I would like to) to external domains while I didn't do anything weird to make that happen.
The only thing I wish for is to receive mails and if you'd ask me, port 25 would be solely for outgoing mails, not for incoming mail deliveries throught MX?
An ISP surely wouldn't disable their customers in having a mail-server for incoming mails, as long as they would send out through their own smtp server to make sure they wouldn't spam the world?
One of our postfix servers is for sending/receiving internal emails only. When a user entered a wrong recipient address, it will take almost an hour for the user to get the "Recipient address rejected" email. What can be done to let the user get the "Recipient address rejected" email quickier.
I'm attempting to send email with a PHP application I got from a textbook. Do I need to start an email server in order to get the application to work?Using SuSE 11.2
Is there a way of allowing only certain domain to send e-mails to certain specific e-mail address. I am using Sendmail, and I have an alias which translate to certain members of staff within my organization. I don't expect e-mails from outside our domain to be sent to this alias e-mail address.
I am setting up a new email server by following the Flurdy guide. I can send but I can't receive. I can telnet in with both the IP address & telnet mail.domain.com 25 I'm not using or loading shorewall because I will be relying on the firewall that is in the router. I have been following the test section of the flurdy tutorial. I am tailing the mail.log file and only see the status as being different from the example
"status=bounced (mail for domain.com loops back to myself)"
It seems like it is getting through to the server but then getting rejected.
i can't receive outside emails on a postfix server. i was able to get it to send emails with help in this thread. i can telnet into it via localhost, but not via domain name.
I am writing an script for sending emails with ssmtp email client in an appropriate form.I want to know how can I check mail server that I want to send mail to it if it exist and ready to receive email or if not log an error.
I just saw that my network is slowed so I watches the /var/log/squid/access.log where I get this line continuously....
[Code]....
I thought that someone running any script so I disconnect all my LAN connection (simply removed the local lan cable) but I saw the connections is going on....so I watch the processes on proxy server but nothing suspicious....So I change my static IP and the spamming stops (I say it is spam b'coz the IP 203.188.197.10 is of yahoomail.com ) but I when I am putting my OLD ip back the connection starts again......I want to put back my old static IP b'coz I have configured it for many services. Is there any spyware on my machine or someone configured my IP?
How to configure my home linux server, as an email server, and be able to send email to hotmail, please?. I have done this before, but I never managed to do it so hotmail accept emails coming from my linux server.
So I have Postfix working great and I've always used webmail if I needed to send email from PC's outside of $mynetworks. So fast forward to today where I got my 1st Android powered mobile phone and I can configure the Android mail client to send/receive IMAP email but my question is do I need to become an open relay to allow my random wireless providers dynamic range of IP's to send mail via Postfix? Seems extremely vulnerable and scary to think I would have to allow my providers IP range to relay mail via my MTA. I started reading a bit and I think I need SASL authentication and since both Postfix 2.8.1 & Dovecot 2.0.11 are both configured / using TLS, is there anything else I would need or you recommend for sending email from my Android powered mobile?
I have postfix sort of working correctly. postfix can send email to the internet but it doesn't want to send email to my local exchange server. What I need is for postfix to send emails directed to @xyz.com to my exchange server instead of itself.
My setup mail.xyz.com - exchange 2003 server www.xyz.com - centos 5.3 server with postfix
www.xyz.com can send emails to my hotmail.com account so that part works correctly. www.xyz.com can't send email to username@xyz.com. postfix seems to be delivering the email to itself and not the exchange server.
How can I tell postfix to send the @xyz.com emails to my exchange server?
Here is a sample of my /var/log/maillog Jul 22 15:43:43 list postfix/smtpd[9802]: D63168604A3: client=localhost.localdomain[127.0.0.1] Jul 22 15:43:53 list postfix/cleanup[9805]: D63168604A3: message-id=<20090722204343.D63168604A3@www.xyz.com>
Our mailing systems was working in web mail and we had a tool wherein if we apply leave mails where sent to web mail. Now we have moved to exchange server and we want the mails to be sent to exchange server. The Leave Management systems is developed in PHP with Mysql the platform used is linux.
I am working happily with Fedora 8, evolution chatting happily to exchange 2003, calendar sync the works...impressed. This continued through Fedora 9 (though a little bumpy as all odd numbered Fedora releases are). On to Fedora 10, yes works a treat out of the box (DVD). A couple of updates to evolution later, through yumex (fedora updates), and evolution has stopped sending email to the exchange server. It's also touch and go whether I can read email using OWA.
On pressing 'Send/Receive' evolution pops the error, Error while performing operation. Exchange transport can only be used with Exchange mail source. How could I back out these evolution updates?
system is RedHat v4. I removed root: admin-name@domain from /etc/aliases then ran /usr/bin/newaliases.
The admin does not get the emails but now the email generated by the cronjobs is being sent to my-name@domain outlook email from "root@localhost.localddomain". No other changes were made. Where should I start looking for the definition of sent crontab email to my-name@domain?
All the emails I send from my linux server end up in the recipient's spam folder....Although I have tried many howtos etc and checked all blacklists... It doesn't work...
My Problem is: I want to stop gmail access without blocking https. Yes in my squid proxy normal [URL].. is not accessible. But gmail recently started https service by which user can still get access to gmail. I DONT WANT TO STOP https CAUSE ITS BEING USING BY OTHER PROGRAMS.
i have been looking up ways to block websites in linux but most all of the free ones only block the sites the software makers want to (or you can't block just the sites you enter without blocking the sites that it wants to)i need to know how to block only websites i enter with squid using webmin
Did anyone heard about or can suggest mabe a postfix serverside solution in order to insert a counter number into the subject line before the message is sent? I mean something similar with helpdesk tickets, because I would like to create the possibility for the senders, to make further refference about a speciffic message using it's counter number provided by postfix server.
I'm attempting to send email used a textbook PHP application. The application fails to send an email.Do I need to setup an email server to get the ap to work?Right now, I'm getting email through Kontact via my web host, Yahoo mail and Google mail.
I don't know what to do, I know how to block and delete pretty much every other type of abuse. I run a server with 500+ shared hosting clients and reseller clients and it was just blocked because of email spam. I can keep on top of all other abuse (people trying to do dos attacks etc) but the one thing I can't get my head around is email spamming. how to stop people spamming emails from my server?