Once we installed Zimbra Collaboration, we need to be aware of some additional configurations that will allow us to send emails to other Email systems with an improve Security, such Gmail, Hotmail, Yahoo!, etc. This Wiki article will show the different Email Protection resources that exists, depends of the volume of sent email, will be better to implement only one, or two, or maybe all of them, depends.
Sender Policy Framework (SPF) is an email validation system, designed to prevent unwanted emails using a spoofing system. To check this common security problem, SPF going to verify the source IP of the email and compare it with a DNS TXT record with a SPF content.
Where needs to be configured?
SPF needs to be configured in the Public DNS Continue reading “Best Practices on Email Protection: SPF, DKIM and DMARC” »
In order to create a multi tenancy in zimbra OSA, can be acheived through a bash script below. Thanks to Ahmad Imanuddin (http://www.imanudin.com) for sharing this very useful script.
Fill with the following line : Continue reading “Zimbra Domain Administration (Multi-tenant)” »
Through zimbraGUI didn’t find it how to do it, but through console it appeared to be working with the following set of commands to modify postfix actually-
zmprov mcf zimbraMtaMaxMessageSize 20971520
zmprov mcf zimbraFileUploadMaxSize 20971520
zmprov mcf zimbraMailContentMaxSize 52428800
zmprov modifyConfig zimbraMtaMaxMessageSize 52428800
Once theyre executed, restart the server (restarting zimbra won’t reflect the changes made, so need a fresh reboot of OS)
Domain Keys Identified Mail (DKIM) defines a domain-level authentication mechanism that lets your organization take responsibility for transmitting an email message in a way that can be verified by a recipient. Your organization can be the originating sending site or an intermediary. Your organization’s reputation is the basis for evaluating whether to trust the message delivery.
You can add a DKIM digital signature to outgoing email messages, associating the message with a domain name of your organization. You can enable DKIM signing for any number of domains that are being hosted by ZCS. It is not required for all domains to have DKIM signing enabled for the feature to work.
DKIM defines an authentication mechanism for email using Continue reading “Using DKIM to Authenticate Email Message” »
To reset the administrative password:
su - zimbra
zmprov sp <admin email address> <new password>
To get a list of all administrators:
su - zimbra
To access the admin console:
Remember that the administrative console (sometimes) requires a full email address as the login name, so you may be using the correct password and the wrong login!
Install SL 6.3 (64 bit)
- Installing SL6.3 (64bit) with 'minimal' installation mode
- Post installing, fix with the Static IP Address (Public IP and I assume the system is not behind firewall)
- Double check with /etc/resolv.conf file parameters
Prerequisites for ZImbra installation
Let's firsy update-
Let's install some pckages as well
yum – y install sudo sysstat gmp libidn libstdc++ bind bind-chroot bind-libs bind-utils wget php perl nc sqlite
and few more packages-
yum install compat-libstdc++-33 sysstat
If anything missed out you'll know in the next steps, if anything left google it, chances are you'll be able to yum it :), however for this time being the environment is made. Now proceed to download Zimbra.
Make some backend job-
- Make sure 'SELINUX' is disabled
- The iptables service is stopped
- 'postfix' service is stopped and disabled at runtime and on boot
My downloaded edition was-
Once downloaded, get inside the extracted folder. Continue reading “Zimbra 8 Community edition on Scientific Linux 6 (64 Bit)” »
Zimbra is a suite of tools for Unix/Linux/MacOS systems, which includes a secure mail server, web mail, anti-spam/anti-virus controls, a Web management interface, integrated calendaring, mobile device sync, and more. In many ways, Zimbra is the Unix equivalent to Microsoft Exchange.
In this post, I will be installing Zimbra onto a CentOS virtual machine. The machine will need at least 1024mb of memory to run the default Zimbra services. I was unable to make it run without errors with any less memory.
Things to do after a clean installation of Centos 5.5:
- Disable SELinux and
- Disable Linux Firewall
The last step is to shutoff some services that will interfere with ZCS.
chkconfig sendmail off
chkconfig ip6tables off
chkconfig iptables off
We need one package before we can continue:
yum install libtool-ltdl
This completes the base installation of CentOS. On the next page we will setup Split DNS which is essential for ZCS. Go ahead and reboot, and fill up that coffee cup. Continue reading “Install Zimbra on Centos 5 Step by step” »
First you need to install a fresh CentOS operating system, keeping almost everything as default state. In this installation note I'm assuming few things-
- There is either a LARGE '/' partion or a LARGE '/opt' partition. Zimbra by default is installed on /opt directory
- I'm also assuming that the server is not sitting beehind a firewall (for example if it's reched by port/ip forwarding from firewall, it won't work). But there are some additional tasks that can allow you to run it behind a firewall. But unfortunately, I won't cover that up here.
- SELinux and Linux firewall, should be disabled for the time being.
- You can install webmin, and from there you can create your custom firewall policy/rule- but you can always do this later, after post installation of Zimbra
Now let's start.
Now we need to shutoff some services that will interfere with ZCS. Continue reading “Step by Step Zimbra 6.x installation on CetOS 5.x” »
1. First you need to su as 'zimbra' user
2. go to /opt/zimbra/bin/
3. Use the following commands to enable SSL:
Now it's working like a charm. For other readers:
I can only access to webclient by SSL now (but that's ok for me).
other options are: