Double-Take Availability requirements

• Operating system—Make sure your servers meet the operating system, kernel, and file system requirements.

   

  Red Hat Enterprise Linux and CentOS

  Operating system version—4.8 through 4.9

  Kernel type for x86 (32-bit) architectures—Default, SMP, HugeMem

  Kernel type for x86_64 (64-bit) architectures—Default, SMP, LargeSMP

  File system—Ext3

  Red Hat Enterprise Linux, CentOS, and Oracle Enterprise Linux

  Operating system version—5.7 through 5.8

  Kernel type for x86 (32-bit) architectures—Default, SMP, Xen, PAE

  Kernel type for x86-64 (64-bit) architectures—Default, SMP, Xen

  File system—Ext3, Ext4, XFS

  Red Hat Enterprise Linux, CentOS, and Oracle Enterprise Linux

  Operating system version—6.2 through 6.3

  Kernel type for x86 (32-bit) architectures—Default

  Kernel type for x86-64 (64-bit) architectures—Default

  File system—Ext3, Ext4, XFS (64-bit only)

  SUSE Linux Enterprise

  Operating system version—10.3 and 10.4

  Kernel type for x86 (32-bit) architectures—Default, SMP, BigSMP, Xen, XenPAE

  Kernel type for x86-64 (64-bit) architectures—Default, SMP, Xen

  File system—Ext3, ReiserFS, XFS

  SUSE Linux Enterprise

  Operating system version—11.1 through 11.2

  Kernel type for x86 (32-bit) architectures—Default, Xen, XenPAE, VMI

  Kernel type for x86-64 (64-bit) architectures—Default, Xen

  File system—Ext3, ReiserFS, XFS

   

  The kernel version must match the expected kernel for the specified release version. For example, if /etc/redhat-release declares the system to be a Redhat 5.5 system, the kernel that is installed must match that.

  Oracle Enterprise Linux support is for the mainline kernel only, not the Unbreakable kernel.

  You must have lsb, parted, /usr/sbin/dmidecode, and /usr/bin/which on your Linux servers before you can install and use Double-Take Availability. See your operating system documentation for details on these packages and utilities.

   

• System Memory—The minimum system memory on each server should be 1 GB. The recommended amount for each server is 2 GB.
• Disk Usage—The amount of disk space required for the Double-Take Availability program files is approximately 85 MB. About 45 MB will be located on your /(root) partition, and the remainder will be on your /usr partition. You will need to verify that you have additional disk space for Double-Take Availability queuing, logging, and so on. Additionally, on a target server, you need sufficient disk space to store the replicated data from all connected sources, allowing additional space for growth.
• Protocols—Your servers must have TCP/IP. IPv4 is the only supported version.
• Ports—Port 1501 is used for localhost communication. Ports 1500, 1505, 1506, 6325, and 6326 are used for component communication and must be opened on any firewall that might be in use.
• IP address and subnet configuration—Because of limitations in the way the Linux kernel handles IP address aliases, do not mix subnets on the eth0 network interface. Failover should not cause problems in this configuration, but you will lose IP addresses during failback. Therefore, if you must mix subnets on a single interface, use eth1 or higher.
• Name resolution—Your servers must have name resolution or DNS. For details on name resolution options, see your Linux documentation or online Linux resources.
• Security—Double-Take Availability security is granted through membership in user groups. The groups can be local or LDAP (Lightweight Directory Access Protocol). A user must provide a valid local account that is a member of the Double-Take Availability security groups.
• SELinux policy—SELinux should be disabled or set to permissive mode on the source and target.
• VMware Tools—Any VMWare guest running Double-Take Availability should have the appropriate VMWare Tools package installed.

The Replication Console can be run on any of the following operating systems.

• Windows 2008
• Windows 2003
• Windows 7
• Windows Vista
• Windows XP Service Pack 2 or later