Appendix: Software install process (from Clearswift online repositories)

The following steps describe how to install the Clearswift SECURE Email Gateway on top of an existing Red Hat Enterprise Linux (RHEL) 6.9 Server (including a suitably configured AWS or Azure instance) using the repositories hosted online by Clearswift. You will need Internet access to complete this installation.

You should install RHEL 6.9 as a Minimal server installation, with a separate /(root) and /var partition. The root partition should be 20GB (minimum) and /var should use a minimum of 60GB for test environments and 200GB for production environments.

To install the Clearswift SECURE Email Gateway:

Assume root role at the command line.
Manually install the cs-email-repo-conf package. The cs-email-repo-conf package configures your system to be ready for you to install the Clearswift SECURE Email Gateway:
```
rpm -ivh http://repo.clearswift.net/rhel6/gw/os/x86_64/Packages/cs-email-repo-conf-3.4.1-2526.x86_64.rpm
```
Forcibly remove postfix, rsyslog and samba V3:
```
yum –y remove postfix rsyslog samba-common
```

Install the required product using the following command:

yum install -y cs-email --enablerepo=cs-*

This command enables access to external repositories and ensures that only Clearswift repositories are subsequently used to install the Gateway.

If Step 5 fails due to additional conflicts, you might need to remove additional packages during Step 4.

Log out completely, and log back in as cs-admin. Refer to Running the First Boot Console to continue.

Post installation considerations

After completing the software install process, the install process might have modified the following parts of your system:

Firewall configuration is now under Gateway control. If SSH access is required you need to re-enable it through the Clearswift SECURE Email Gateway user interface. See Configuring SSH Access in the Clearswift SECURE Email Gateway online help for more information.
All network configuration is now under Server Console control. You should avoid changing network configuration at the command line as the Gateway is not notified of these changes. If changing network configuration at the command line is necessary, please contact Clearswift Support for more information.
crontab configuration is modified. Pre-existing root cronjobs might be lost, but you can re-add them.

After a software installation...

The software installation process will not automatically disable any of your pre-existing repository configurations. From the command line you will be able to install additional third-party software in the normal way. This includes additional RedHat software.

From version 4.6 onwards, you will only be able to apply Clearswift-provided upgrades using the Clearswift Server Console. Server Console will ensure that only trusted Clearswift repositories are used during the upgrade process and will explicitly block any unintended updates from third-party repositories during the process.