The following operating systems are supported by Enswitch:

• CentOS.
• Debian GNU/Linux.
• Fedora.
• Redhat Enterprise Linux (requires Redhat subscription).
• Ubuntu.

Enswitch supports both 32 and 64 bit operating systems. When installing machines, please:

• Use a fresh Linux installation.
• If possible, configure the disks as RAID1 for reliability. If the machine has 4 disks, please use 2 as RAID1 for the root filesystem, and 2 as RAID1 for a separate filesystem for the database or NFS files. Database filesystems should be mounted on /var/lib/mysql, and NFS filesystems on /var/lib/enswitch.
• Install the minimum set of packages to get the machines on the internet, plus:
  • An SSH daemon so we can connect in remotely.
  • A mail transport agent (MTA). Sendmail is reported to work best out of the box, but Exim and Postfix can also be used. Please test that each machine can send emails to internet addresses, and that the headers on the emails are correct.
• Hostnames must be lower-case only, match the machines' DNS entries, and be unique within the Enswitch cluster.
• Do not create an "enswitch" user; the Enswitch installer expects to create this user for daemons to run as.
• Do not install Asterisk, Kamailio, OpenSIPS, OpenSER, MySQL, or Apache. The Enswitch installation process will install fresh versions. If these are already installed, we will ask you to wipe the machine and re-install Linux.
• If your Linux distribution automatically installs any extra daemons such as X windows or network servers, disable them. This improves both performance and security.
• Use static IP addresses, not DHCP.
• Disable ACPI in the BIOS settings or grub menu.
• Put the machines directly on the internet, not behind a firewall, even if the firewall claims to support VoIP. Have the public IP addresses configured on the servers themselves rather than on a machine in front of them. We configure iptables based firewalling on each machine as a standard part of the installation.