There are many methods of remotely controlling servers but the KVM (keyboard, video, mouse) switch offers the most immediate access and is one of the simplest to implement. Designed to remotely control up to 32 servers, the latest Dominion KVM (keyboard, video, mouse) switches from Raritan support KVM over IP connections, and deliver a range of useful features including improved performance, tight security and basic fault tolerance.
The Dominion KX216 on review provides sixteen RJ-45 KVM over IP ports. Access options are very good as the switch provides PS/2, USB and video ports for local access to connected systems, and supports up to two simultaneous links from administrators over the network. Each server is connected to the switch via a CIM (computer interface module) - a short plug with a network port at one end, and sockets for mouse, keyboard and monitor at the other. Raritan provides CIMs for both Windows and Sun servers with either USB or PS/2 sockets. These are purchased separately, with the PC USB or PS/2 versions costing around £70 each.
The switch has a pair of 10/100BaseTX network ports with the first activated by default. Should it fail for any reason, the second automatically takes over and uses the same IP address. If the entire network goes down you can still reach your servers as the switch supports a serial port modem, allowing administrators to dial for an out-of-band management session.
Installation starts with a local connection where you access the switch's on-screen display (OSD) menu using a hot-key combination and select an IP address for the first network port. You can also use the OSD to display all channels, swap between KVM ports and directly control the attached system. Each channel can be given a meaningful name, and local access can be controlled with password-protected user profiles. There's not much else to do here and unlike much of the competition you can't implement a scan mode where the switch automatically swaps between channels after a specific dwell time.
Full access via Java
Although the OSD only provides basic administrative access to the switch, Raritan's Java-based Dominion KX Manager provides full access. This is used to set up general security by creating user and group access control lists and you can decide which channels can be accessed, whether the connected device can be controlled, or viewed, and what functions are available. You can also select SSL authentication and encryption combinations as well.
Power control is available with Raritan's optional PCR modules with the eight-port model costing around £450. This must be configured from the KX Manager, but the supplied manuals were so bad we were only able to set the PCR module up after contacting Raritan's support. The PCR module connects to the switch via its own CIM cable and once each power socket has been associated with a server you can manage power although all you can do is power the server up and down and recycle power.
Raritan's Java-based Remote Client utility offers remote access over the LAN and provides good security as SSL encryption is extended even to video traffic. The main browser interface is a simple affair with a basic tree down one side showing all available KVM ports and their connection status and remote control sessions can be started immediately simply by selecting the relevant channel. Two global modes are provided for determining whether connections can be shared. In Private mode the switch will only allow one networked or local user to access a channel, whilst the PC Share mode allows all users to share the channel.
Remote control performance is comparatively smooth although we did occasionally have problems synchronising the mouse pointers. Tools are provided for calibrating and modifying video parameters, and profiles are used for setting up network and dial-up connections. Keyboard controls are provided so you can send standard key press combinations to the remote system and macros are also supported.
There is plenty of choice in the KVM switch market and KVM over IP is now the preferred method of remote connection. The Dominion KX216 scores well with its high level of security measures but we also found overall performance was good and management tools are above average for the price.
In server farms and data centres attaching a local monitor, mouse and keyboard to each system can be an unnecessary expense. It makes far more sense to control them from a central location and the Dominion KVM switches offer an excellent range of management features backed up with good security.