F. A. Q. - Recent questions and answers in Linux

Answered: How to Hide Zimbra/Disallow Index from Search Engines?

Sat, 02 Dec 2023 04:54:52 +0000

I found this useful information from Zimbra forum and Zeta alliance milist. These script will prevent search engine like Google to hide or disallow index Zimbra webmail.

If you type “Zimbra webmail” on Google, you will find a lot of Zimbra webmail from some organizations that indexed by Google.

zmprov mcf +zimbraResponseHeader "Strict-Transport-Security: max-age=31536000; includeSubDomains"
zmprov mcf +zimbraResponseHeader "X-XSS-Protection: 1; mode=block"
zmprov mcf +zimbraResponseHeader "X-Content-Type-Options: nosniff"
zmprov mcf +zimbraResponseHeader "X-Robots-Tag: noindex"
zmprov mcf zimbraMailKeepOutWebCrawlers TRUE
zmmailboxdctl restart

If you run above script, it will be one method to prevent your Zimbra server from a target .

Answered: How to Use Proxmox Mail Gateway with an Authenticated Smarthost

Tue, 22 Aug 2023 01:55:00 +0000

by joel · October 6, 2018

The Proxmox email gateway GUI allows you to set a non-authenticated smarthost.

I’ve been using the excellent Proxmox mail gateway to filter spam for our CareTech email server. Since I haven’t decided, yet, to pay our ISP their monthly charge for a static IP address, I can not send mail directly and have to relay through a smarthost. The Proxmox Mail Gateway interface allows you to set a smarthost but offers no provision for relaying with SMTP authentication. If you need to authenticate with your smart host, you’ll need to spend some time with the command line. Let’s get started.

1. Let’s take care of software dependencies first. You need to install a SASL library that’s not included by default; if you skip this step, you’ll see errors in your Postfix log and authentication will fail. Update software package information, and then install “libsasl2-modules.”

apt-get update

apt-get install libsasl2-modules

2. Change to the /etc/postfix/ directory and create a file to store the hostname, username, and password of your relay host; and set secure permissions on the file. It doesn’t matter what you name the file; just use a name that makes sense to you. I’ve chosen to call it “relay_passwd.”

cd /etc/postfix

touch relay_passwd

chmod 0600 relay_passwd

3. Edit the file using your favourite command-line editor, and enter just one line in precisely this format (replacing your relay server, port number, username, and password with your own information):

[smtp.example.com]:587 username:password

4. Save and close the file. Then, hash the newly created password file to make a db file Postfix can use:

postmap relay_passwd

5. Make a backup copy of your main.cf file in case you mess things up and need to restore known-good configuration. I like to date-stamp my configuration file backups, like so. Replace with today’s date.

cp main.cf main.cf.2018-10-06

6. Edit main.cf and add the following lines. Again, replace the “smtp.example.com” host name with the actual host name of your smart host; use the correct port number; and pay attention to the file name.

relayhost=[smtp.example.com]:587

smtp_use_tls = yes

smtp_sasl_auth_enable = yes

smtp_sasl_password_maps = hash:/etc/postfix/relay_passwd

smtp_sasl_security_options =

7. Restart Postfix, and test your new configuration.

systemctl restart postfix

8. Does it work? Great! Now, note that the main.cf file is written by the Proxmox web interface and the next time you make settings changes in the web interface affecting Postfix config, the lines you just added will be over-written and lost. To make this change permanent, you’ll need to edit the main.cf template file. Change to the /var/lib/pmg/templates directory and edit the main.cf file there, making exactly the same edits you made to the /etc/postfix/main/cf file. This will ensure that next time Proxmox writes out config file changes, it will include your custom lines and your authenticated smarthost relay will keep on working.

Answered: How to use Amazon SES to send mails to specific domains in Zimbra

Wed, 26 Jul 2023 10:30:26 +0000

Quite a good one, it requires fiddling with zimbra and postfix and unfortunately requires some manual configuration. I suppose you can handle the amazon stuff for getting an account.

all commands are done on the cli as the zimbra user. So login with ssh and become zimbra user by

su - zimbra

create an file for authentication to amazon:

echo email-smtp.eu-west-1.amazonaws.com awsauthuser:awsauthpass > /opt/zimbra/conf/relay_password
postmap lmdb:/opt/zimbra/conf/relay_password

Configure zimbra to use this username and password:

zmprov mcf zimbraMtaSmtpSaslPasswordMaps lmdb:/opt/zimbra/conf/relay_password
zmprov mcf zimbraMtaSmtpSaslAuthEnable yes
zmprov mcf zimbraMtaSmtpCnameOverridesServername no
zmprov mcf zimbraMtaSmtpTlsSecurityLevel may
zmprov mcf zimbraMtaSmtpSaslSecurityOptions noanonymous

Create a lookup file where you put the domains you want to send via amazon:

echo outlook.com smtp:email-smtp.eu-west-1.amazonaws.com > /opt/zimbra/conf/relay_amazon
postmap lmdb:/opt/zimbra/conf/relay_amazon

Of Course, you can add extra domains to the list above in an editor of your liking. Remember to run the postmap command after every change.

Tell zimbra to use the above mapping:

zmprov mcf zimbraMtaTransportMaps lmdb:/opt/zimbra/conf/relay_amazon,proxy:ldap:/opt/zimbra/conf/ldap-transport.cf

Activate the configuration

zmmtactl reload